Description, Detection, and Classification of Hawaiian Monk Seal Vocalizations Through Deep‐Learning Methods: Biological and Conservation Applications - Jeppe Have Rasmussen; Jillian M. Sills; Kirby Parnell; Colleen Reichmuth (Marine Mammal Science, 2026)
The Hawaiian monk seal is a phocid Carnivore endemic to the Hawaiian Archipelago. This species was thought to be silent under water until the recent discovery that mature males produce at least six distinct calls year round, typically in bouts of two or more, with sound production linked to reproductive status. Here, we apply a progressive deep‐learning approach for acoustic monitoring of this endangered marine mammal, based on vocalizations obtained from two adult seals housed separately in controlled settings. We used 4989 manually labeled calls and corresponding spectrogram images to fine‐tune a pre‐trained YOLO network via transfer learning to detect and classify sounds from long‐term recordings of the same individuals. The algorithm demonstrated 87% weighted precision and efficiently recovered 48,324 calls from 16,262 h of data. This dataset was then queried to confirm temporal trends in vocal activity and predictable patterns in call sequencing. We transitioned this approach to field settings by combining verified calls from the laboratory with soundscape recordings at a range of signal‐to‐noise ratios. The re‐trained algorithm recovered 2049 seal vocalizations from 12 h of recordings from critical habitats with varying background noise levels, successfully capturing the temporal patterns in acoustic presence documented by manual annotations. This machine‐learning tool enables the informed use of acoustic data to detect free‐ranging Hawaiian monk seals, supporting conservation efforts for this endangered species.

Social Arousal and Interspecific Calf Handling by Short‐finned Pilot Whales - Agathe Serres; Mingming Liu; Mingli Lin; Hongri Wang; Xiuqing Hao; Songhai Li (Marine Mammal Science, 2026)

Mind the Gap: Performance Limits of Automated Contour Extraction Methods for Individual Monitoring of Bottlenose Dolphins - Saskia C. Tyarks; Matthew D. Hyer; Frants H. Jensen (Marine Mammal Science, 2026)
Reliable extraction of dolphin whistle contours is fundamental for scalable analyses of vocal identity, repertoire structure, and individual‐based acoustic monitoring. We evaluated four algorithms for fundamental frequency estimation of common bottlenose dolphin ( Tursiops truncatus ) whistles, leveraging a benchmark dataset of annotated whistles from known animals to assess performance across individuals and as a function of signal‐to‐noise ratio (SNR). In high‐SNR whistles (> 20 dB), the deep learning models CREPE‐tt, SAM‐whistle, and Silbido Profundo achieved similar performance in mean contour coverage (~80%), with CREPE‐tt producing the most continuous contours and the lowest frequency error. SAM‐whistle and Silbido Profundo were more robust than CREPE‐tt under low‐SNR conditions. However, automatically extracted contours consistently reduced within‐ versus between‐individual separation and ultimately decreased individual classification accuracy, highlighting how contour gaps and fragmentation propagate into downstream identity matching. Taken together, our results suggest a practical division: CREPE‐tt excels with high‐SNR data and detailed contour shape analyses without harmonic post‐processing, whereas SAM‐whistle and Silbido Profundo perform better with low‐SNR recordings. For individual identification and abundance estimation, explicit SNR‐based inclusion thresholds and quality‐control criteria remain necessary.

Beyond Rare: Documenting Albino‐Like Phenotypes as a Recurring Trait in the Juan Fernandez Fur Seal - Constanza Toro‐Valdivieso; Renato Borras‐Chavez; Víctor Castillo‐González; Luciano Hiriart‐Bertrand; Michael E. Goebel; Barbara Blacklaws (Marine Mammal Science, 2026)

Behavioral Response of Arctocephalus australis to Pedestrian Disturbance During the Breeding Season: Implications for Wildlife Tourism Management - Maite Arangüena‐Proaño; Carlos Calvo‐Mac; Yann Tremblay (Marine Mammal Science, 2026)
The South American fur seal ( Arctocephalus australis ) breeds in dense colonies along the Peruvian coast, mostly within protected areas managed by the Servicio Nacional de Áreas Naturales Protegidas por el Estado (SERNANP). To support responsible wildlife tourism near breeding sites, we evaluated the behavioral responses to controlled pedestrian approaches at Punta Coles, within the Reserva Nacional Sistema de Islas, Islotes y Puntas Guaneras (RNSIIPG). Specifically, we (a) quantified A. australis responses to pedestrian disturbance and (b) identified the factors influencing variation in individual alert distance (i.e., the distance at which animals first detect and respond to human presence) during the breeding season. We conducted 61 standardized approaches across five colonies, recording synchronized video, GPS tracks, and sound‐level measurements, and obtained wind conditions from satellite‐derived data. Linear models with stepwise Akaike Information Criterion (AIC) selection identified the key predictors of alert distance. Alert distance increased with colony size, and was greater when wind conditions favored human scent transport toward the colony (i.e., smaller wind‐track angle difference). These results underscore the importance of sensory cues and colony‐size effects in shaping human–pinniped interactions, consistent with antipredator and vigilance theory. The empirical relationship derived here provides a practical, transferable framework for establishing evidence‐based buffer distances to guide sustainable pinniped tourism.

Comparing Drone and Vessel‐Based Imaging to Quantify Epibiont Coverage on Humpback Whales - Isabel A. R. Taylor; Ticiana Fettermann; Barry McGovern; David S. Schoeman; Adrian B. McCallum; Stephanie H. Stack (Marine Mammal Science, 2026)
Cetacean epibionts offer noninvasive insights into host health, physiology, and spatial ecology, yet quantitative assessments in wild populations remain scarce. Although vessel‐based observations may be limited by field of view and analyst input, unoccupied aerial vehicles (UAVs; drones) are increasingly used to monitor cetacean health indices, enhancing observational availability and reproducibility. However, the suitability of drones for quantifying epibiota has not been thoroughly evaluated. Implementing a standardized workflow, we compared dorsal proportional epibiont coverage estimates derived from drone‐based imagery and traditional vessel‐based techniques across reproductive classes of humpback whales ( Megaptera novaeangliae ). We analyzed 32 paired datasets using pixel‐based methods, incorporating semiautomated graph‐cut segmentation and iterative color‐thresholding. Drone‐derived estimates of epibiont coverage consistently exceeded vessel‐based measures, which averaged 58% of the relative coverage estimated from corresponding drone imagery, partly attributable to variable lighting during image capture. Nevertheless, 94% of paired observations differed by less than 5% in absolute coverage, indicating strong agreement. While refinement of flight parameters, image resolution, and further validation are recommended, we demonstrate that drones can provide a reliable source of quantitative epibiont data, with potential applicability across diverse epibiont–host systems, benefiting cetacean population health monitoring programs and informing conservation strategies, particularly for elusive or understudied species.

Humpback Highs and Lows Amid Shifting Seas and a Northeast Pacific Marine Heatwave: Whale Demographics in the Main Hawaiian Islands, 2002–2023 - S. M. Barber‐Meyer; T. Cheeseman; J. Barlow; L. Bejder; A. L. Bradford; R. Cartwright; M. Deakos; L. Evans; R. Finn; C. M. Gabriele; B. Goodwin; C. Hayslip; et al. (Marine Mammal Science, 2026)
North Pacific humpback whales are a celebrated conservation success, rebounding from extensive commercial whaling. Yet they remain vulnerable to the impacts of climate change, a multifaceted stressor that can exacerbate existing threats. During 2013–2016, a Northeast Pacific marine heatwave severely reduced forage availability in their feeding grounds, concurrent with diminished whale recruitment and increased mortality. We analyzed photo‐identification data of whales that visited the Main Hawaiian Islands from 2002 to 2023 to estimate apparent survival, abundance, and distinct population segment (DPS) growth rates. Survival was high prior to (0.987; SE = 0.003), low during (0.684; SE = 0.022), and higher, but still reduced, after (0.956; SE = 0.006) the heatwave. Annual breeding season abundance estimates averaged 11,617 (SD = 1914) and included a striking 37% decrease from 2014/15 to 2021/22. While the average annual DPS growth rate was stable (1.00) over 20 breeding seasons, shorter periods included high growth (1.09) and steep decline (0.783). Depressed survival and abundance estimates may signal lingering heatwave effects or adjustment to current carrying capacity. Climate change predictions include more frequent, intense, and longer heatwaves; thus, this DPS serves as a crucial ecosystem‐health indicator. Continued research and monitoring are essential to support resiliency against future climate perturbations.

Sex Ratio, Pregnancy Status, and Blubber Testosterone Concentrations of Humpback Whales ( Megaptera novaeangliae ) on Foraging Grounds in the Southwestern Atlantic - Henry W. Slesser; Joanna L. Kershaw; Amy S. Kennedy; Caroline R. Weir; Stephanie Martin; Emma L. Carroll; C. Scott Baker; Manuela Bassoi; Danielle L. Buss; Martin Collins; Jennifer A. Jackson (Marine Mammal Science, 2026)

Aquaculture Systems Affect the Impact of Probiotics, Prebiotics, and Synbiotics on Growth and Immunity of Oreochromis niloticus : A Systematic Review and Meta‐Analysis - Diego Cardenas Laverde; Ruth Yolanda Ruiz Pardo; Luisa Marcela Villamil Diaz (Reviews in Aquaculture, 2026)
Tilapia ( Oreochromis niloticus ) aquaculture is expanding worldwide, yet disease, environmental variability, and the need for sustainable production remain major challenges. Biotics, including probiotics, prebiotics, and synbiotics, have been explored to enhance growth and immunity, but their effectiveness across aquaculture systems is not fully understood. This systematic review and meta‐analysis examined 141 studies, including 96 with quantitative data, to identify consistent biological responses of different biotics. Probiotics were the most studied and consistently effective additives, improving weight gain, feed conversion ratio, and immune performance across diverse production environments. Synbiotics and prebiotics provided additional benefits, though less consistently. Synbiotics sometimes produced larger effects with higher variability, while prebiotics showed moderate average effects; however, the small number of available studies, substrate heterogeneity, and wide uncertainty limited confidence in their reproducibility. Immunological and biochemical analyses revealed increased lysozyme, superoxide dismutase, and catalase activities, along with reduced alanine transferase, supporting enhanced antioxidant and hepatoprotective capacity. Production system emerged as an important source of heterogeneity across studies, with closed systems displaying more consistent growth‐related responses than open systems, suggesting that the biological effects of probiotics may be system dependent. Overall, probiotics represent the most widely used and reliable strategy to enhance tilapia health and performance, while closed systems appear to provide more stable conditions for growth‐related responses. However, further research using transcriptomic approaches, such as RNA sequencing, is needed to clarify the molecular mechanisms underlying system‐dependent responses.

Ecological Reasons for the Unusually High Rate of Gastropod Drill Hole Repair in the Deep‐Sea Brachiopod Abyssothyris wyvillei From New Zealand - Jeffrey H. Robinson; Angela J. Brandt (New Zealand Journal of Marine and Freshwater Research, 2026)
Brachiopods are able to repair drill holes made in their shells by predatory gastropods. However, in most samples examined, drill hole repair is rare to absent: Presumably the drilling attack is usually fatal to the prey. The shells of short‐looped brachiopod Abyssothyris wyvillei , from deep‐sea dredge samples from two localities in the Tasman Sea, New Zealand, show both a high rate of drilling by muricid gastropods and an unusually high rate of drill hole repair, with some specimens having multiple repaired drill holes. Abyssothyris is one of the largest and most common bivalved organisms collected at the two stations. Examination of the molluscan taxa from the same samples revealed the presence of three species of muricid, one large and two small. The much higher number of muricid drill holes in Abyssothyris shells (129) than in molluscan shells (11) and the small size of the drill holes in Abyssothyris shells (0.15–0.8 mm) suggests that the two small muricid species targeted Abyssothyris as a preferred prey species. The majority of repaired drill holes occur over a smaller shell size range (0.15–0.5 mm), and statistical analysis shows this to be significant. This is interpreted as juvenile to young gastropods making successful drilling attacks on Abyssothyris but their appetite not being sufficient to inflict a mortal wound on their much larger prey, and the brachiopods are then able to repair the drill holes.

Issue Information (New Zealand Journal of Marine and Freshwater Research, 2026)

Remote Sensing With Machine Learning to Monitor Seagrass Meadows: Long‐Term Trends in Tauranga Harbour, New Zealand - Zhanchao Shao; Karin R. Bryan; Sanne M. Vaassen; Conrad A. Pilditch; Brooke Ellis‐Smith; Josie A. Crawshaw (New Zealand Journal of Marine and Freshwater Research, 2026)
Seagrass meadows play critical roles in coastal ecosystems by stabilising sediments, supporting biodiversity and sequestering carbon, yet monitoring their recovery at scale is often constrained by the lack of scalable and repeatable approaches. This study applies an open‐source remote‐sensing framework to track long‐term changes in Zostera muelleri in Tauranga Harbour, New Zealand, from 1959 to 2024. Using supervised machine learning (Random Forest) applied to Landsat and Sentinel‐2 imagery, combined with regression‐based estimates of seagrass density, we generated maps of seagrass extent and condition with overall accuracies of 0.88 for Sentinel‐2 and 0.77 for Landsat across all habitat classes. Beyond total area, the approach resolved changes in meadow structure, including patch size, connectivity, fragmentation and interannual variability, providing a landscape‐scale perspective on seagrass dynamics. Comparisons with manual aerial‐photo delineations supported the reliability of the broad harbour‐wide patterns. The combined record showed a 49% decline in seagrass extent between 1959 and 1990, followed by strong recovery since 2016, with extent exceeding 4,000 ha in 2023 and accompanied by recent subtidal expansion. The observed recovery occurred alongside documented management actions and variation in sediment‐related conditions, while preceding‐season temperature was positively associated with summer subtidal extent. The framework provides managers and practitioners with a repeatable means of monitoring long‐term seagrass recovery and informing adaptive coastal management.

Unravelling β‐Diversity and the Role of Small Streams in Shaping Fish Communities Using a National‐Scale eDNA Database - Lovisa Genevieve Ekelund; N. C. Boddy; J. Brasington; R. G. Death; I. Barrett (New Zealand Journal of Marine and Freshwater Research, 2026)
The role of river size on fish communities remains underexplored in freshwater ecology. Small streams, despite accounting for 75% of stream length, are more vulnerable to human impacts and often lack legislative protection. Nevertheless, they can serve as refuges and rearing areas for fish, including rare or threatened species. To understand if small streams host distinct fish assemblages, we analysed fish β‐diversity across stream sizes using a publicly available eDNA database. At a national scale, we calculated ‘local contributions to β‐diversity’ (LCBD) to assess site distinctiveness and ‘species contributions to β‐diversity’ (SCBD) to evaluate species‐specific impacts on compositional variation. We further partitioned β‐diversity into turnover and nestedness components at the catchment scale to explore underlying mechanisms of community change. Our findings support the hypothesis that low‐order streams host more distinct fish assemblages than medium‐ or high‐order streams. At a catchment scale, compositional differences were more often driven by turnover and associated to stream order and distance to sea. We found a negative relationship between the proportion of diadromous species and community distinctiveness, suggesting these species may homogenize communities. Contrary to expectations, introduced species were associated with higher LCBD values, likely reflecting an invasion‐driven community reshuffling. Interpreting these patterns requires careful consideration of species’ traits, historical biogeography, and anthropogenic effects. Together, these results highlight the critical role of small streams in maintaining fish diversity and the importance of protecting them.

Age‐ and Growth‐Based Life‐History Traits of Striated Surgeonfish ( Ctenochaetus striatus ) and Achilles Tang ( Acanthurus achilles ) from Miti‘āro, Cook Islands - Antony Vavia; Elizabeth D. L. Trip; Valerio Visconti; Julian Lilkendey; Jingjing Zhang; Charlie Owen; Armagan Sabetian (New Zealand Journal of Marine and Freshwater Research, 2026)
Striated surgeonfish ( Ctenochaetus striatus ) and Achilles tang ( Acanthurus achilles ) are two surgeonfish species commonly harvested for subsistence on Miti‘āro, Cook Islands. Using individuals collected by local fishers, this study provides the first age‐ and growth‐based assessment of these species from Miti‘āro. Age and size distribution of C. striatus ranged from 1 to 27 years and 105–250 mm (FL), respectively. Age and size distribution of A . achilles ranged from 0 to 9 years and 137–215 mm (FL), respectively. Von Bertalanffy growth function (VBGF) models estimated asymptotic lengths of 185.18 mm for C. striatus and 183.11 mm for A. achilles . Likelihood ratio tests and 95% confidence ellipses of VBGF parameters ( L ∞ and K ) indicated no significant differences in growth between males and females for either species. Length–weight analyses showed C. striatus exhibited slightly negative allometric growth, while A. achilles displayed an isometric relationship. Annual mortality was estimated at ~36% for both species. These findings provide new insights into the life‐history and population dynamics of key reef fish targeted for subsistence in the Cook Islands.

Beyond Blue Carbon: Estimating the Value of Ecosystem Services Provided by Coastal Wetlands in Aotearoa New Zealand - Phoebe Stewart‐Sinclair; Zoe Qu; Orlando Lam‐Gordillo; Richard Bulmer; Vonda Cummings; Carolyn Lundquist (New Zealand Journal of Marine and Freshwater Research, 2026)
Blue carbon ecosystems (BCE), including mangroves, saltmarshes, and seagrasses, provide essential functions and services globally but are increasingly challenged by climate change and other anthropogenic activities. In Aotearoa New Zealand (Aotearoa NZ), there is mounting interest in blue carbon as a nature‐based solution to climate change. Quantifying the monetary co‐benefits of BCE, in addition to carbon sequestration, can help illustrate the relative contribution of ecosystem services provided by existing habitats, as well as the potential additional value associated with restoration. Here, we estimated the value of provisioning, regulating, and cultural ecosystem services provided by BCE in Aotearoa NZ. We found that the most valuable ecosystem service provided by mangroves was carbon sequestration, while in saltmarsh and seagrass, the most valuable ecosystem services were waste treatment and existence, bequest values, respectively. Unit monetary valuations of ecosystem services range from NZD 3 ha −1 yr −1 (water flow regulation) to NZD 32,590 ha −1 yr −1 (climate regulation) for mangroves, NZD 8 ha −1 yr −1 (spiritual experience) to NZD 23,045 ha −1 yr −1 (waste treatment) for saltmarshes, and NZD 3 ha −1 yr −1 (water regulation) to NZD 14,512 ha −1 yr −1 (existence, bequest values) for seagrasses. The estimated national potential monetary value of ecosystem services provided by current habitats ranges from NZD 0.8–995 million yr −1 for mangroves (30,533 ha nationally), NZD 0.2–482 million yr −1 for saltmarshes (20,932 ha nationally), and NZD 0.2–216 million yr −1 for seagrasses (61,340 ha nationally). If drained areas were restored from drained agricultural use, values would increase accordingly. These results apply the benefit transfer approach (applying monetary values from analogous temperate ecosystems globally to estimate values in Aotearoa NZ) to generate indicative monetary benchmarks, which can help inform discussions around investment in BCE and long‐term coastal climate change adaptation decision‐making in Aotearoa NZ.

Age‐Based Life Histories of Epinephelus fasciatus , Lethrinus obsoletus , and Siganus punctatus From the Commercial Fishery of Guam, Micronesia - Brett M. Taylor; Cassandra Pardee; John Wiley; Leilani Sablan (New Zealand Journal of Marine and Freshwater Research, 2026)
Age‐based life‐history information provides a foundation for evaluating population dynamics and vulnerability of coral reef fishes, yet many commercially important species from the tropical western Pacific remain poorly characterized. In this study, we examined the age, growth, and reproductive life histories of three reef‐associated species harvested in Guam's commercial fishery: the blacktip grouper Epinephelus fasciatus , the orangestripe emperor Lethrinus obsoletus , and the goldspotted spinefoot rabbitfish Siganus punctatus . All specimens were obtained through the NOAA‐funded commercial fisheries biosampling program, with a total of 120 L. obsoletus , 110 E. fasciatus , and 97 S. punctatus sampled from local markets. Age estimates were derived from sagittal otoliths, and reproductive parameters were assessed through gonadal examination. Despite differences in trophic guilds, all three species reached similar asymptotic fork lengths (26.1, 26.7, and 24.7 cm, respectively), and females of all species matured at approximately 20 cm fork length. Maximum observed ages were 13 years for E. fasciatus and L. obsoletus and 10 years for S. punctatus . Growth trajectories differed markedly among species, with the two carnivorous taxa exhibiting slower growth rates relative to the herbivorous rabbitfish, resulting in a younger age at maturation for S. punctatus . These results highlight both shared and contrasting life‐history traits among cooccurring reef fishes with similar body sizes but contrasting trophic guilds. Over the past 15 years, age‐based research on coral reef fisheries in the southern Mariana Islands has expanded rapidly, and these species fill critical gaps within an increasingly comprehensive life‐history framework that underpins biologically informed assessments of stock status and vulnerability.

A Surprising Diversity of Aquatic Oligochaetes (Annelida: Clitellata) on Campbell Island/Motu Ihupuku (New Zealand), With a Checklist of Sub‐Antarctic and Antarctic Microdrile Oligochaetes - A. M. Pinder; R. M. Schmelz; S. McMurtrie; A. James (New Zealand Journal of Marine and Freshwater Research, 2026)
Campbell Island/Motu Ihupuku, 650 km SW of New Zealand, was surveyed for freshwater invertebrates during the austral summer of 2010/11 as part of the Campbell Island Bicentennial Expedition. Aquatic oligochaetes constituted a considerable proportion of the species collected. A total of 19 species were recorded, including 6 Naididae, 9 Enchytraeidae, and 4 Phreodrilidae, bringing the total number of microdrile species known from freshwater habitats on the island to 20. At least nine are known only from this island. Two new genera and four new species are described, with other specimens also likely representing undescribed species. The island's fauna has biogeographic affinities with other islands in the Southern Ocean/sub‐Antarctic and high latitude regions of southern continents, such as Macquaridrilus (also from Macquarie Island), Biprostatus (also from Tasmania) and Phreodrilidae which primarily inhabits Gondwanan landmasses and southern oceanic islands. Several species are likely human introductions. Species richness on Campbell Island greatly exceeds that of Macquarie Island, where only six species have been documented. Interpretation of the origins of this diversity and comparisons with other islands is hampered by inadequate knowledge of worm faunas from other islands and even from high latitude regions of some southern hemisphere continents.

Seasonal Patterns and Environmental Drivers of Seagrass ( Zostera muelleri ) Flowering in Aotearoa New Zealand: Implications for Seed‐Based Restoration - Dana E. Clark; Dan Crossett; Jessica Barr; Demi Fearn; Georgia Cotter; Javier Atalah; Susie Hine; Eleanor Brettle; Irisa Hudson; Maureen Ho; Sophie Whittall; Al Alder; et al. (New Zealand Journal of Marine and Freshwater Research, 2026)
Seagrass flowering underpins seed‐based restoration and is governed by the interaction of multiple abiotic and biotic drivers operating across a range of temporal and spatial scales. In New Zealand/Aotearoa, flowering was historically considered rare, but emerging evidence indicates it is more widespread than previously recognised, creating new opportunities for restoration. We conducted a 4‐year study from 2022 to 2025 across three estuaries near Nelson, New Zealand, to investigate how seasonality, seagrass cover, tidal height and regional temperature anomalies influence Zostera muelleri flowering density and identify peak flowering periods within each intertidal system. Flowering occurred within a broadly predictable seasonal window, with mean peak inflorescence densities (11 ± 3.1 SE to 170 ± 53.2 m −2 , maximum 756 m −2 ) observed between November and January at the beginning of Austral summer. A generalised additive model showed that seagrass cover was the strongest and most consistent predictor of flower density, with denser meadows supporting significantly greater numbers of flowers. Tidal height and temperature anomalies further influenced flowering in some estuaries, with higher flowering density occurring higher on the shore and reduced flowering associated with both warmer‐ and cooler‐than‐average temperatures. Peak flowering densities recorded in high‐flowering years were comparable to those reported from some Australian meadows of the same species, where seed‐based restoration approaches are being trialled, suggesting that meadows in New Zealand can exhibit comparable reproductive capacity under favourable conditions. These results provide the first extensive assessment of seagrass flowering dynamics in New Zealand, offering fundamental ecological insights and practical guidance for optimising seed‐based restoration domestically and worldwide.

Plastic Inputs to Lake Rotorua: An Initial Assessment of Stormwater Stream Plastic Loads and Capture Devices - Aria Kerebs; Margaret Armstrong; Deniz Özkundakci (New Zealand Journal of Marine and Freshwater Research, 2026)
Plastics are a known but inconsistently researched challenge to Aotearoa New Zealand's inland freshwater systems. Understanding plastic origins, movement, and removal options for individual water bodies can enhance management efforts. This exploratory study quantified meso‐ and macroplastics entering Lake Rotorua through stormwater streams and assessed suitability of in‐stream capture devices. Plastic samples were collected and analysed over five sampling events at seven Rotorua city stormwater sites. Of the 306 samples (5982 g total), 51 were made of recyclable polymers, 124 were nonrecyclable and 131 were unidentifiable (e.g., degraded). Significant differences (ANOVA) were observed between the sample counts and weights of some sites (e.g., Depot Street and Headwater). With plastics present in the stormwater streams, capture devices are one option for collecting and removing pollution. A literature review was conducted to ascertain what aquatic‐based devices are being used globally and which are suitable for the stormwater streams. Six Rotorua‐based criteria (e.g., suitability in narrow or shallow channels) identified booms and boom‐receptable devices as recommended for trialling. Study findings can support reassessment of ongoing initiatives in Rotorua city and guide further scientific research. These insights can also be applied to meso‐ and macroplastic pollution in lakes with similar urbanised catchments.

Limited Success of Spat Ropes and Rubber Ramps for Restoring Fish Passage at a Perched Culvert - Sjaan Bowie; Nixie Boddy; Cindy F. Baker; Jonny Horrox; Paul A. Franklin (New Zealand Journal of Marine and Freshwater Research, 2026)
Many culverts in New Zealand rivers are poorly designed or maintained, impeding fish migrations. This study tested three low‐cost fish passage solutions—mussel spat ropes, a flexible rubber ramp, and a combination of both—at a perched culvert apron on the West Coast. Passage efficiency was assessed for three indicator species with different locomotive capabilities: īnanga ( Galaxias maculatus ), redfin bully ( Gobiomorphus huttoni ), and banded kōkopu ( Galaxias fasciatus ). Spat rope and rubber ramp both independently and in combination were ineffective at facilitating passage of īnanga or redfin bully. The combination of spat rope and rubber ramp moderately increased banded kōkopu passage, predominantly for fish

What Do New Zealanders Think About Freshwater Fish? Results From a National Survey - Marc Tadaki; Alaric McCarthy; Fabio Weiss; Aisling Rayne; Sarah Crowley; Alexis Farr; Leah Gibbs; Jane Kitson; Nick Reo; Philip Stahlmann‐Brown (New Zealand Journal of Marine and Freshwater Research, 2026)
The 2025 Environmental Perceptions Survey provides unique insight into a nationally representative sample ( n = 1024) of New Zealanders’ perceptions of freshwater fish. About 8% of the sample had fished in the past 12 months and 30% had fished ever, and fisher subsamples were more male, more Māori and younger than the New Zealand population. Perceived awareness of local freshwater fish presence was higher for fishers than non‐fishers for all species, but both shared highest awareness of eel/tuna, whitebait and trout, which are also the most commonly fished species. Assessment of national fishing popularity and fishing pressure was mixed, but regional trends are evident. Respondents agreed that there are not enough freshwater fish, that fishers should be able to eat what they catch and that fish are healthy enough to eat. Respondents prefer more of all freshwater fish species rather than only one or two species. This data can help understand how people's relationships with freshwater and fish are changing and possibilities for building alliances for freshwater stewardship.

Sea Urchin Removal as a Tool, Not a Solution: Practical Lessons for Kelp Restoration in Aotearoa New Zealand - Kelsey I. Miller; Arie J. P. Spyksma; Celia A. Balemi; Alice McSherry; Leigh Takirau; Vince C. Kerr; Aaron M. Eger; Nicholas T. Shears (New Zealand Journal of Marine and Freshwater Research, 2026)
The increasing awareness of the extent of urchin barrens and impacts of sea urchin overgrazing on rocky reefs in Aotearoa New Zealand has led to a rapid increase in the use of sea urchin removal as a tool for kelp forest restoration. Here, we review these restoration projects, focusing on three case studies, with the aim to provide context on what urchin removal does and does not achieve and guidance on when, where and how it might be both ecologically and culturally appropriate. At least fifteen known iwi Māori, hapū, community and research‐led urchin removal projects are underway nationally. We consider multiple components of the urchin removal process, including respect for Māori practice and traditions, large‐scale practicality, and ecological effectiveness. Urchin removal from urchin barrens is labour intensive but can promote rapid kelp recovery. However, without addressing the cause of sea urchin overpopulation (i.e. overfishing of sea urchin predators), kelp recovery is temporary as sea urchins will eventually return. Ongoing removals may provide longer‐term benefits but not a fully functioning and resilient kelp forest ecosystem. Therefore, urchin removal is best used as part of well‐planned, iwi‐supported and permitted restoration projects including marine protection. Finally, we caution that urchin removal should not detract or take away from restoration strategies to address the root cause of sea urchin overpopulation, particularly the rebuilding of predator populations.

Supplementary Diet of DL‐Methionine and Electro‐N as Antistress to Improve Growth Rates and Immune Responses of Red Hybrid Tilapia ( Oreochromis mossambicus × Oreochromis niloticus ) Juveniles Reared Under High Densities - Mohamed F. Abdel‐Aziz; Shyma M. Shalaby; Esraa A. Yacoub; Youmna M. Abdo; Gad H. G. Hussein; Mohamed A. Elokaby; Dalia S. Hamza; Ashraf Y. El‐Dakar (New Zealand Journal of Marine and Freshwater Research, 2026)
Immunostimulantsare essential in aquaculture because they strengthen the immune system, enhance disease resistance, and improve the health of cultured aquatic species, especially under poor water quality and stressful conditions. They also promote better growth, survival, and antibody production without harmful side effects. As a safe alternative to antibiotics, immunostimulants support sustainable aquaculture and healthier fish farming practices. So, the current study was conducted to improve the performance of red tilapia fingerlings reared under stressful conditions of high densities by using commercial additives of methionine (MET) and a commercial antistress (Electro‐N, Elec). A 60‐day feeding trial including seven experimental diets was formulated as follows: a 30% crude protein basal diet without additives (T0), a basal diet supplemented with 0.5% MET (T1), 1.0% MET (T2), and 1.5% MET (T3). The same tested concentrations of MET with the addition of 0.5% Elec per (T4) 0.5% MET‐Elec, (T5) 1.0% MET‐Elec, and (T6) 1.5% MET‐Elec. Juveniles were within an initial average weight of 18.07 g ± 0.25 (SE) and randomly stored in 21 plastic tanks (60 L) at a rate of 20 fish/tank (60 fish/treatment). The data obtained suggested that dietary MET supplemented with or without Elec improved the growth, survival rate, and body content of protein, hematological characteristics, intestinal digestive enzymes, and immunity functions of fish in comparison with the control group. Specifically, a fish‐fed diet containing 1% MET with 0.5% Elec had a balance between the best survival rate and growth performance, indicating that this treatment had the best indicators of physiological and immunity functions.

From Genogroups to Control Strategies: A Comprehensive Review of Piscirickettsia salmonis and Piscirickettsiosis to Optimize Health Management in Salmonid Aquaculture - Marco Rozas‐Serri (Reviews in Aquaculture, 2026)
Piscirickettsiosis, caused by the facultative intracellular bacterium Piscirickettsia salmonis , remains the primary infectious disease economically limiting salmonid aquaculture in Chile, while its incidence has also increased in farmed salmonids in Ireland, Scotland, Australia, and Canada in recent years. This comprehensive review synthesizes 181 peer‐reviewed publications (2014–2026) to integrate transformative advances in P. salmonis genomics, pathogenesis, epidemiology, host immunity, and control strategies, updating the foundational 2014 review by Rozas and Enríquez. Comparative genomic studies have consistently resolved LF‐89‐like and EM‐90‐like isolates as two distinct phylogenomic clusters, with marked differences in pan‐genome composition, lineage‐specific proteins, ribosomal operon organization, and Dot/Icm‐associated genomic architecture, supporting genogroup‐level divergence that should not be inferred from any single threshold‐based metric such as Average Nucleotide Identity (ANI) alone. Genogroup‐specific disease phenotypes are also well established. LF‐89 produces chronic granulomatous infections, whereas EM‐90 causes acute hemorrhagic septicemia. Mechanistically, P. salmonis evades cell‐mediated immunity by inhibiting phagosome–lysosome fusion and suppressing MHC‐I–mediated antigen presentation, impairing CD8 + cytotoxic T‐lymphocyte priming and likely explaining the consistently low vaccine efficacy and genogroup‐restricted cross‐protection observed under field conditions. Treatment failures persist despite absent widespread acquired resistance, attributable to intracellular persistence, biofilm formation, and pharmacokinetic–pharmacodynamic mismatches. Despite exponential growth in mechanistic knowledge, a substantial translational gap persists between research findings and operational implementation. This review identifies critical priorities requiring urgent investment: genogroup‐specific bivalent vaccine development, climate‐adaptive biosecurity frameworks, molecular diagnostic standardization for real‐time genogroup surveillance, and integrated control strategies tailored to P. salmonis genomic heterogeneity.

Genome Manipulation in Microalgae: A Systematic Map on Improved Traits, Strains, and Their Commercial Applications - Irene Gallego; Michael Meissle; Jörg Romeis (Reviews in Aquaculture, 2026)
Microalgae are promising platforms for producing diverse biocompounds relevant to multiple commercial sectors, and the use of genomic technologies in microalgae is rapidly expanding. To examine the research trends, we conducted a bibliographic analysis (systematic map) of this rapidly developing field. Our study presents a descriptive overview of genomic techniques in microalgae for industrial applications, highlighting emerging trends and key knowledge gaps. After the initial identification of more than 23,600 scientific publications, we screened over 5,500 original research studies that were deemed most relevant by AI‐based sorting. We then selected 518 relevant studies in which microalgal strains were genetically modified to improve traits of commercial interest. We also compiled information on industrially relevant sectors that potentially benefit from genetically improved microalgae. Overall, more than 60 strains from 10 genera, mainly belonging to green microalgae, cyanobacteria and diatoms, were genetically improved for future commercial applications. Most studies used conventional genetic engineering techniques, with incipient research on gene editing tools. The most frequently improved microalgal traits varied with the type of cell (eukaryotic microalgae vs. cyanobacteria). Genetically improved eukaryotes (mainly green microalgae) produced proteins, lipids and pigments, while cyanobacteria synthetized alcohols, polyols and terpenoids. The main recipient of the improved strains is the human health sector, followed by the bioenergy sector, food and beverage industries, animal farming including aquatic animals, and cosmetics. Manufacturers of bioplastic packaging, chemical industries, environmental remediation companies, wastewater treatment plants, and the agriculture sector may also benefit from the use of genetically improved microalgae and their derived products.

Sustainable Integrated Multi‐Trophic Aquaculture: Key Considerations for Assessing Environmental and Economic Performance - Sara Hornborg; Fabrizio Capoccioni; Xavier Irz; Markus Langeland; Arianna Martini; Domitilla Pulcini; Fredrik Salenius; Friederike Ziegler (Reviews in Aquaculture, 2026)
Integrated multi‐trophic aquaculture (IMTA), defined as the co‐production of species at different trophic levels, is conceptually appealing. By utilising complementary functions of different species, it holds opportunities for lower environmental impact, higher productivity, and increased profitability in comparison with conventional monoculture. However, whether those advantages materialise in practice remains unclear. Here we review available life cycle assessment (LCA) and cost–benefit analysis (CBA) studies of IMTAs to further the current understanding of environmental and economic performance. We find that, overall, LCAs conclude that IMTAs investigated have not been able to deliver on environmental promises, while CBAs generally find that IMTAs have both better financial performance and lower environmental externalities than monoculture equivalents. The main reasons for these contrasting findings include the nature of the systems assessed so far—often theoretical or experimental set‐ups with non‐optimised designs—combined with methodological choices in assessments. The findings of the review thus suggest that it is still unclear to what extent IMTA can deliver on its promises in practice, and that IMTA is no panacea for aquaculture but requires careful design to be effective for its intended use. Integrating robust LCAs and CBAs early in the development phase can help identify viable IMTA set‐ups based on key drivers of environmental and economic performance and, in this way, minimise the risks of misaligned practices. A first step towards realising the potential of IMTA is to carry out robust assessments that avoid key mistakes in both LCAs and CBAs, to which end we provide hands‐on recommendations for future assessments.

Issue Information (Reviews in Aquaculture, 2026)

A Systematic Review of Studies Investigating the Transmission Dynamics of Infectious Salmon Anemia Virus - Ahsan Raquib; Persia Carol Thapa; K. Larry Hammell; Javier Sanchez; Nicole O'Brien; Krishna Kumar Thakur (Reviews in Aquaculture, 2026)
Infectious salmon anemia is one of the most important viral diseases affecting the farmed Atlantic salmon industry. The objectives of this systematic review were to appraise the methods, parameters, and validation approaches employed in mathematical modeling studies related to infectious salmon anemia virus (ISAV) transmission dynamics, identify limitations among them, and suggest recommendations for future modeling approaches. A total of 898 studies were identified through the search of four databases and Google Scholar, and five government reports were added to this list after manually checking the reference list of full‐text articles. After removal of duplicate studies, title and abstract screening, and full‐text screening, 24 studies were finally included in the systematic review. The included studies mostly used mechanistic models ( n = 16), followed by hybrid models ( n = 5); only three studies used statistical models. We categorized the objectives of the modeling studies into four categories: prediction of ISAV spread, model parameterization, persistence of ISAV, and effectiveness of control interventions. Most studies tried to predict ISAV spread and estimate model parameters. Our review identified several limitations in existing models, including a lack of calibration and validation with real‐world data, reliance on deterministic frameworks, inconsistent use of compartment structures, and failure to incorporate many key ISAV transmission pathways. Existing modeling studies have substantially advanced our understanding of ISAV spread and informed control strategies. Future research should aim to overcome current limitations by estimating key transmission parameters, such as the basic reproduction number ( R 0 ) across seasons and viral genotypes, and by incorporating stochastic modeling approaches.

Grass Carp Reovirus ( GCRV ): Biology, Immune Responses and Control Strategies - Waqar Younas; Mijuan Shi; Rong Huang; Yaping Wang; Libo He; Hong Yang; Lei Zhang; Yingyin Cheng; Wanting Zhang; Lanjie Liao; Yongming Li; Bin Gui; et al. (Reviews in Aquaculture, 2026)
As the world's population grows, aquaculture is becoming a rapidly growing source of protein. Grass carp ( Ctenopharyngodon idella ) is one of the most important aquacultured species in China and has emerged as a significant commercial fish worldwide. However, grass carp reovirus (GCRV) poses a significant threat to grass carp aquaculture. This review covers GCRV biology, phylogeny, pathogenesis, immune response pathways, therapeutic approaches, and future challenges and directions. A comprehensive phylogenetic analysis describes the structure of GCRV, its entry into cells, its molecular architecture, its replication procedures and its interactions with the host, with a particular focus on the pivotal role of Pattern Recognition Receptors (PRRs). The paper explores how PRRs, such as RLRs (RIG‐I and MDA5) and TLRs (TLR3 and TLR19), are essential for identifying GCRV and initiating robust antiviral responses, particularly the interferon pathway. The paper goes on to explain the complex immune evasion tactics employed by GCRV, emphasizing how viral proteins such as VP41, VP4 and VP56 selectively target and interfere with critical components of PRR signaling cascades, such as MAVS‐TBK1 and MITA/STING, thereby reducing host immunity. Various next‐generation vaccines are being developed, including DNA, subunit, VLP and oral/mucosal platforms. These are supported by Chinese herbal and chemical antivirals. According to CRISPR/Cas9, experimental RNAi, PI4KB and SOCS3a/3b are host genes that can be altered to increase grass carp resistance to GCRV. This research offers significant insights into viral cell invasion and strengthens innate and adaptive immunity, enabling safer, more practical and multilayered control in aquaculture.

Fish Sperm Subpopulations Detection, Separation, and Application: Current State and Trends - Viktoriya Dzyuba; William V. Holt; Borys Dzyuba (Reviews in Aquaculture, 2026)
Sperm subpopulations represent a fundamental manifestation of intra‐ejaculate heterogeneity in fish, arising from differences in structural features, motility patterns, and physiological states of sperm cells. This variability is increasingly recognised as biologically significant, influencing fertilisation success, sperm competition, and egg selection. Advances in computer‐assisted sperm analysis, flow cytometry, and fluorescent staining have enabled the identification of distinct subgroups based on kinematic, morphological, and biochemical traits. However, techniques for their physical separation and functional assessment remain in early development for fish, limiting their routine application in aquaculture. Understanding sperm heterogeneity offers innovative perspectives for reproductive biology, providing insights into species with complex mating strategies and guiding the refinement of aquaculture practices, particularly in situations where sperm quality is reduced or highly variable. Applications include optimising artificial fertilisation, improving cryopreservation protocols, and enhancing genetic stability by isolating high‐quality subpopulations, especially when optimal volumes of high‐quality sperm are not available. Importantly, sperm subpopulation analysis also holds promise for conservation programs, where selecting and preserving viable gametes is critical for maintaining genetic diversity and supporting the recovery of endangered and threatened fish species. By reducing abnormal larval development and improving fertilisation efficiency, this approach strengthens hatchery success and contributes to long‐term sustainability. Overall, framing sperm heterogeneity as both a biological phenomenon and a biotechnological resource highlights its importance and innovation. This review synthesises current knowledge, explores possible origins of sperm subpopulations, and outlines future directions for their application in aquaculture and conservation, with particular relevance in contexts where reproductive performance is compromised or variable.

Amino Acids in the Natural Food Web of Global Fishponds: Way Forward for Precision Protein Feeding in Pond Cyprinid Aquaculture - Md. Foysul Hossain; Katerina Sezimova; Jan Mraz; Radek Gebauer; Lubos Zabransky; Koushik Roy (Reviews in Aquaculture, 2026)
Natural food webs in freshwater pond ecosystems provide an important nutritional foundation for cyprinid aquaculture, yet information on their protein and amino acid composition remains fragmented. This review synthesized published data from 30 studies (1950–2026) reporting protein and indispensable amino acid (IAA) composition of freshwater natural food resources, including algae, zooplankton, and zoobenthos. Protein and IAA concentrations were standardized on a dry matter basis and evaluated relative to common carp ( Cyprinus carpio ) amino acid requirement benchmarks. Natural food protein quantity and quality followed the trophic pattern zooplankton > zoobenthos > algae. The IAA profiles in zooplankton and zoobenthos mostly met or exceeded common carp dietary benchmarks, unlike algae which may fall short. Relative trophic position (RTP) was positively associated with all IAAs, supporting the concept of trophic upgrading within freshwater food webs. Lysine exhibited the strongest relationship with RTP ( R 2 = 0.551), demonstrating a high sensitivity to natural food choices by pond carp, whereas methionine showed the weakest relationship, strictly controlled across trophic levels, making it one of the most difficult IAAs to source in pond food web. Our analysis suggests that any ideal protein concept for supplementary feed for ponds should be centered around methionine (as denominator), as most supplementary pond feed protein ingredients may exacerbate the methionine deficiencies and undermine protein utilization. A nutritional ecology framework integrating food web IAA into precision pond feed, with complementary ingredient choices, can greatly enhance the efficiency and cleanliness of pond aquaculture.

Can AI Write Your Next Review? Yes. Does That Make Real Review Articles Redundant? No - Giovanni M. Turchini (Reviews in Aquaculture, 2026)

High‐Throughput Sequencing in Aquaculture Disease Investigations: Challenges and Opportunities for Implementation - Francisca Samsing; Phoebe Arbon; Matthew Arnold; Andrew C. Barnes; David Bass; Joy A. Becker; Jerusha Bennett; Charles Caraguel; Jeremy Carson; Vincenzo A. Costa; Thomas Dumond; Jemma Geoghegan; et al. (Reviews in Aquaculture, 2026)
The current generation of sequencing technologies can produce terabases of data with exceptional accuracy and speed, at a fraction of the cost of older methods. Despite this unprecedented power, adoption into aquaculture health management presents several challenges, including identifying where such capability may be optimally deployed. Here we synthesise discussions from a structured expert workshop held at the 2025 Aotearoa Aquatic Diseases Symposium in Dunedin, New Zealand, where experts from industry, government and academia explored the challenges and opportunities for adopting high‐throughput sequencing (HTS) to support disease investigations in aquaculture. Workshop participants identified key applications for HTS, including pathogen discovery during unexplained mortality events and source attribution in epidemics, but also noted technical, regulatory and social challenges for widespread adoption. These include the need for standardised sampling and bioinformatic workflows, data sovereignty, equitable access to the technology and uncertainty around interpreting detection of notifiable pathogens. Targeted research and coordinated regulatory frameworks will be essential to guide responsible use of HTS and determine where it adds value relative to existing approaches. Clarifying these opportunities and constraints will guide the responsible adoption of HTS into aquaculture health management to support sustainable growth for the sector.

An Update on Advancement in Genomics Resources for Spiny Lobster Aquaculture Development - Courtney Lewis; Ahmad Farhadi; Susan Glendinning; Thomas Banks; Tara Kelly; Andrew G. Jeffs; Sandra Infante Villamil; John Breen; Jennifer M. Cobcroft; Arya Vazirzadeh; Basseer M. Codabaccus; Chris G. Carter; et al. (Reviews in Aquaculture, 2026)
The rapid advancement of high‐throughput sequencing technologies has transformed aquaculture genomics, enabling unprecedented insights into the biology and improvement of non‐model aquatic species. Among crustaceans, lobsters represent one of the most commercially valuable yet genomically underexplored taxa. This review synthesises the current state of genomic and transcriptomic resources available for spiny and slipper lobsters (Achelata), contextualising these within the broader decapod framework. We outline key genomic assemblies, transcriptomic atlases, and molecular tools that underpin emerging research on reproduction, nutrition, growth, stress tolerance, and disease resistance. We further highlight how omics‐driven approaches—spanning whole‐genome sequencing, SNP discovery, RNA interference, and nutrigenomics—are reshaping opportunities for selective breeding, reproductive control, and feed optimisation. Recent progress in establishing closed‐cycle aquaculture of Panulirus ornatus now provides the foundation for applying these molecular resources to address key production bottlenecks, including larval duration, cannibalism, and asynchronous moulting. We propose future directions integrating genomics, transcriptomics, and functional tools to accelerate sustainable domestication and genetic improvement of lobsters. Together, these advances mark a pivotal shift toward genomically informed spiny lobster aquaculture.

Multipathway Pesticide Exposure and Cross‐Scale Risk Assessment in Integrated Rice–Crab Aquaculture - Dan‐Dan Bian; Shi‐Rong Li; Bo‐Ping Tang; Qiu‐Ning Liu (Reviews in Aquaculture, 2026)
Integrated rice–crab co‐culture represents a sustainable agroecosystem, yet a critical conflict arises: pesticide applications necessary for rice cultivation undermine the health of the co‐cultured Chinese mitten crab ( Eriocheir sinensis ) and jeopardize system sustainability. To address this challenge, a comprehensive analytical framework is developed, linking multipathway pesticide exposure, molecular toxicity mechanisms, cross‐scale risk assessment, and resilience‐oriented governance. This framework systematically reviews the environmental fate and exposure dynamics of pesticides in paddy fields, as well as their toxicokinetics and tissue‐specific bioaccumulation in E. sinensis . Moving beyond descriptive toxicology, the study integrates “effect hierarchy” and “mechanistic network” perspectives to unravel cascading toxicity pathways, spanning oxidative stress, neuroendocrine disruption, cellular pyroptosis, and immune suppression. The limitations of conventional risk assessment in such a complex system are critically examined, with emphasis on the dual risks to crab population resilience and human food safety. To mitigate these challenges, a novel, mechanism‐informed “Prevent–Intercept–Protect–Adapt (PIPA)” framework is proposed to bolster system resilience, combining green pest control, eco‐engineering, host health enhancement, and smart monitoring. This review enhances theoretical understanding of contaminant impacts in multitrophic systems and offers actionable management strategies to promote the sustainable development of integrated aquaculture.

Decoding the Black Box of Fish Vaccines Efficacy in Basic and Applied Contexts - Jiří Kyslík; Mikolaj Adamek; Tomáš Korytář (Reviews in Aquaculture, 2026)
Vaccines are the frontline defense in aquaculture, yet predicting their real‐world performance remains a tricky puzzle. Unlike terrestrial veterinary vaccines, fish vaccines largely operate through “Black Box” processes, where we observe the outcomes but rarely understand the underlying immune mechanisms. Laboratory trials, though informative, often fail to capture the complexity of commercial farms, where environmental fluctuations, pathogen diversity, host genetics, and stressors interact. Field studies provide glimpses into vaccine performance, but they are sparse, short‐term, and sometimes biased, leaving many questions unanswered. Environmental stressors, particularly reuse water, low oxygen, ammonia accumulation, and fluctuating temperatures, can undermine even well‐designed vaccines. Handling, vaccination stress, and the developmental stage of the fish further influence immunity, explaining why the same vaccine may succeed in one setting and fail in another. Immunologically, vaccine success depends on effective antigen processing, a balanced mix of systemic and mucosal responses, and durable memory, yet these factors are rarely measured in the field. Mucosal vaccines show promise by targeting pathogen entry points, while systemic responses remain essential for broad protection. This review explores the “Black Box” nature of fish vaccines, in which vaccination inputs and protective outcomes are observable, yet the internal interactions among environmental factors, host biology, and immune mechanisms remain poorly defined. Unlocking these factors is key to turning unpredictable vaccines into reliable tools for sustainable disease control in a growing aquaculture industry.

An Overview of Post‐Translational Modifications in Aquatic Animal Immunity and Pathogen Evasion - Jiayang Lin; Ming Guo; Chenghua Li (Reviews in Aquaculture, 2026)
As aquaculture continues to expand and intensify, infectious diseases are increasingly viewed as a major constraint on sustainable and high‐quality production. In aquatic animals, post‐translational modifications (PTMs) serve as central regulatory layers of innate immunity by tuning immune sensing, signal transduction, downstream defense execution, and tissue homeostasis. This review brings together recent advances in PTM‐related disease‐resistance research across teleosts, crustaceans, mollusks, and echinoderms, with particular attention to viral, bacterial, and parasitic infections. We focus on phosphorylation and ubiquitination as two major regulatory mechanisms that tune the activation threshold, signal intensity, and termination of immune signaling at conserved but unevenly characterized nodes within RLR‐, TLR‐, cGAS–STING‐, and JAK–STAT‐related pathways. Rather than acting through a single shared mechanism, these PTMs regulate aquatic immune responses through pathway‐specific kinase activation, phosphatase‐mediated restraint, ubiquitin‐chain editing, and protein turnover. Beyond phosphorylation and ubiquitination, we also discuss other PTMs, including methylation, acetylation, SUMOylation, ISGylation, glycosylation, and lipidation, which may contribute to immune homeostasis, tissue repair, barrier protection, and host–pathogen adaptation in context‐dependent ways. Pathogens, meanwhile, can exploit PTM‐dependent checkpoints by targeting host kinases, altering ubiquitin‐dependent protein turnover, interfering with transcriptional or cytoskeletal regulation, or using their own surface glycosylation and lipidation patterns to modify host recognition. Finally, we consider emerging directions, including PTM‐focused proteomics, functional validation by gene‐editing approaches, metabolism‐linked modifications, and PTM‐informed biomarkers, to clarify host–pathogen interactions in aquatic animals and inform future strategies for disease control in aquaculture.

Environmental and Biological Factors Shaping Fish Swimming Ability: Insight From a Meta‐Analysis on Endemic Fish in China - Yuanming Wang; Hongtao Wang; Pengcheng Li; Xintong Li; Ruifeng Liang; Kefeng Li (Reviews in Aquaculture, 2026)
Fish swimming ability serves as a robust proxy for physiological assessment and species conservation. Numerous rivers with a large spatial span and diverse fish species in China complicate the efforts to understand swimming ability and challenge the protection of fish populations. One hundred and sixty‐four relevant studies over the past 15 years, involving 30 families and 126 distinct test sites, were identified to provide a comprehensive overview of fish swimming ability in China. Specifically, test sites geographically concentrated in the Yangtze River basin and Cyprinidae received the most research attention. The basin, family, altitude, living condition, and body length exerted considerable effects on fish swimming ability. Fish from the continental basin had the highest induced swimming speed ( U ind ), whereas those from the southwest basin showed outstanding critical ( U crit ) and burst ( U burst ) swimming speeds. U ind did not differ significantly at the family level, while Cyprinidae and Cobitidae outperformed other families in U crit and U burst . U ind was lowest at an altitude of 2328–3588 m, while U crit and U burst followed unimodal trends, peaking at altitudes of 622–1343 m. Test apparatus and protocols had a limited effect on fish swimming ability, only except that swimming speeds in Brett‐type flumes were higher than that in pipe channels or straight flumes. The living condition did not affect U ind while wild Cyprinidae exceeded cultured Cyprinidae in U crit and U burst . Overall, this study identified factors contributing to fish swimming ability differences and their variation patterns, deepening our knowledge on fish swimming ability and informing fish conservation strategies in China.

Syndromic Convergence in Aquaculture Disease Management: A Critical Review of Climate‐Pathobiome Interactions, Diagnostic Frameworks, and Knowledge Gaps - Ilhan Altinok (Reviews in Aquaculture, 2026)
Aquaculture disease management is increasingly confronted by complex, multi‐factorial outbreaks that resist explanation under the conventional “one pathogen, one disease” framework derived from Koch's postulates. This review introduces syndromic convergence (SyCo) as a formal conceptual framework defining disease states in which climate‐driven environmental stressors, host immune competence, and interacting pathogen communities (pathobiomes) synergistically produce disease syndromes qualitatively distinct from the sum of individual pathogen effects. Drawing on documented outbreaks in salmonids, penaeid shrimp, Mediterranean marine species, and freshwater finfish, it is demonstrated that SyCo events, characterized by synergistic mortality exceeding 1.5× that of any single pathogen, cannot be adequately diagnosed or managed using single‐agent surveillance systems or reductionist intervention strategies. It is proposed a five‐criterion quantitative scoring matrix (0–10 scale; threshold ≥ 8) for SyCo classification, a tiered confidence‐rating system for climate‐virulence mechanisms, and a Syndromic Convergence Early Warning Index (SC‐EWI) integrating water quality, microbiome dysbiosis, behavioral signals, and stressor history into a composite farm‐level risk score. A three‐layer precision intervention framework, environmental mitigation, host immune priming (including nanovaccines and trans‐generational immune priming), and pathobiome‐targeted biologicals (RNAi and phage cocktails), is proposed as operationally aligned with the SyCo model. Seven priority knowledge gaps are identified, including validation of the scoring matrix against outbreak data, quantification of the EHP‐ Vibrio dose–response axis, characterization of maternal microbiome contributions to trans‐generational immune priming, and development of multi‐target dsRNA constructs for co‐infection scenarios. Collectively, this framework advances a transition from reactive, single‐pathogen pathology to predictive, convergence‐aware biosurveillance in global aquaculture.

Commercially Exploited Seaweed Species in Africa: Occurrences, Chemical Composition, Current Value Chain and Opportunities for Value Addition - Mondli Abednicko Masanabo; Marthe Jordbrekk Blikra; Trond Løvdal; Dagbjørn Skipnes; Morten Sivertsvik; Aditya Parmar; M. Naushad Emmambux (Reviews in Aquaculture, 2026)
Africa has a wide range of coastal environments that support a diverse array of seaweed species. Despite this, only a few African countries are involved in the commercial harvesting and value addition of seaweed. Instead, most of the seaweed harvested in Africa has been exported as dried seaweed for value addition. This review discussed the different seaweed species commercially exploited in Africa, their nutritional composition, their current and potential uses as food, paying attention to food safety aspects regarding heavy metals and microbiological safety, and their use as animal feed ingredients and as sources for the production of polysaccharides, proteins, and biostimulants. It was noted that many factors limit seaweed value addition in Africa, including limited access to financial capital, a lack of seaweed research activities, a lack of seaweed storage and processing facilities, limited technical capacity, and weak domestic markets. Thus, in this review, the authors suggested that seaweed value addition in Africa should be regional (East, South, West, and North Africa), driven by species largely grown in those regions. These suggestions can leverage existing value chains across different regions in Africa. To achieve this, more regional cooperation among countries producing similar species is necessary, knowledge sharing on best farming practices, and more research on chemical composition, safety (microbial, heavy metals, microplastics), and efficacy, as well as funding and policy for human capital skill development and the technical skills necessary for seaweed processing.

Macroalgae and Bivalve Interactions: A Review of Trophic and Feeding Studies to Assess the Contribution of Macroalgal Detritus to Bivalves - Fiona P. MacKechnie; Andrew G. Jeffs (Reviews in Aquaculture, 2026)
There is growing interest in the co‐culture of macroalgae and filter‐feeding bivalves due to anticipated trophic benefits that may enhance the productivity of both organisms. Detritus from cultured macroalgae has the potential to supplement bivalve diets, yet few studies have directly examined this relationship in co‐culture systems. This review synthesizes findings from over 70 studies encompassing a broad range of macroalgae and bivalve species to assess the potential for macroalgal material to contribute to bivalve nutrition. No consistent patterns of macroalgal utilization by bivalves were found across regions, seasons, bivalve taxa, or macroalgal groups. In situ trophic assessments using stable isotopes and fatty acids produced divergent estimates of macroalgal dietary contributions, averaging 23.7% and 6.1%, respectively. Feeding studies of bivalves fed various forms of macroalgal material found that while relatively high rates of assimilation efficiency were measured for some bivalve species, the generally poor performance of bivalves in longer term feeding studies strongly indicated that the nutritional composition of the macroalgal material is insufficient, and/or that the macroalgal material contains compounds that actively inhibit bivalve growth. The majority of feeding studies found that regardless of the diet preparation method or species of macroalgae used, bivalve growth was reduced when macroalgae was incorporated at rates higher than a 25% replacement of feed dry weight. Overall, the findings point toward a generally limited potential for filter feeding bivalves to benefit significantly from co‐culture with macroalgae, although specific pairing of macroalgae and bivalve species may derive greater advantage from co‐culture.

Defining Threshold Limits for Multiple Abiotic Stressors in Fisheries and Aquaculture Systems - Neeraj Kumar; Rinku Dey; Mukesh Bhendarkar; Kotha Sammi Reddy (Reviews in Aquaculture, 2026)
Aquatic ecosystems are increasingly exposed to multiple abiotic stressors driven by climate change, environmental degradation, and anthropogenic activities. These stressors, including temperature fluctuations, dissolved oxygen depletion, pH alterations, ammonia accumulation, salinity changes, excessive stocking density, and contamination by inorganic and organic pollutants, can adversely affect fish physiology, growth, reproduction, immunity, and survival. The objective of this review is to synthesize current knowledge on threshold limits of major abiotic stressors relevant to fisheries and aquaculture systems and to evaluate their individual and interactive effects on aquatic organisms. The review highlights substantial interspecific variation in tolerance limits, greater sensitivity of early life stages, and the importance of considering multiple stressor interactions when defining sustainable environmental thresholds. Evidence indicates that rising temperatures can intensify contaminant toxicity, reduce dissolved oxygen availability, and alter salinity and ammonia dynamics, thereby increasing physiological stress in aquatic organisms. A comprehensive literature survey was conducted using major electronic databases, including Google Scholar, Scopus, Web of Science, ScienceDirect, and PubMed. Relevant peer‐reviewed research articles, review papers, and technical reports published over the past seven decades were identified using appropriate keywords and Boolean search operators. Understanding these threshold limits is essential for developing science‐based management strategies, improving fish welfare and production efficiency, and supporting adaptive policies for sustainable fisheries and aquaculture under changing environmental conditions. Interestingly, we anticipate that this review will serve as a valuable reference for researchers, aquaculture practitioners, policymakers, and other stakeholders involved in the sustainable management of aquaculture and fisheries resources.

Autophagy in Aquatic Animals: A Double‐Edged Sword in Environmental Stress Response and Nutritional Mitigation Strategies - Hui Gao; Yue Liu; Xiuling Li; Wenxia Wang (Reviews in Aquaculture, 2026)
The intensification of aquaculture and global climate change expose aquatic animals to multifaceted environmental stressors, triggering diverse stress‐response cascades to mitigate cellular damage and preserve physiological homeostasis. Autophagy, an evolutionarily conserved lysosome‐dependent catabolic process that degrades damaged or redundant cellular components to maintain cellular homeostasis and physiological functions, plays a crucial role in the environmental stress response in aquatic animals. This review systematically summarizes the modulatory influence of major environmental stressors (physical, chemical, and biological) on autophagic activity in aquatic species. Overall, the regulatory network mainly centers on oxidative stress responses, mitochondrial quality control, the 5′‐adenosine monophosphate‐activated protein kinase (AMPK)/mechanistic target of rapamycin kinase complex 1 (mTORC1) signaling axis, mitogen‐activated protein kinase (MAPK) cascade, endoplasmic reticulum (ER) stress and related pathways. The dynamic equilibrium of autophagic flux dictates the cellular fate balance between adaptive survival and stress‐induced injury: physiologically moderate autophagy functions as a cytoprotective and adaptive mechanism that confers stress resilience, whereas dysregulated autophagy (either impaired flux or excessive activation) disrupts cellular homeostasis and shifts cell fate toward apoptotic death. Additionally, this review explores the potential of nutritional intervention strategies to modulate autophagic activity and alleviate stress‐induced damage in aquatic animals. Finally, key challenges and prospective research directions are proposed, providing a theoretical framework for deciphering stress resistance mechanisms in aquatic animals and advancing sustainable aquaculture practices.

An Investigation Into the Seasonality and Quality of Food on Marina Pontoon Structures for the Candidate Marine Biological Control Agent, Lunella smaragda (Gastropoda) - Lauren M. Fletcher; Grant A. Hopkins; Matthew R. Miller; Natalí J. Delorme; Rebecca M. McMullin; Lizenn Delisle; Javier Atalah (New Zealand Journal of Marine and Freshwater Research, 2026)
This study investigates how food availability aligns with nutritional requirements of the snail Lunella smaragda , a potential biological control agent for managing biofouling in recreational vessel hubs. Biofouling communities were assessed during two contrasting seasons to gain insights into the quantity and quality of food available for agent consumption. Nutritional availability was higher in spring/summer and increased with biofouling age, whereas the increase plateaued after 32 days of the 54‐day deployment period in autumn/winter. Biofouling communities were predominantly composed of saturated fatty acids, with proportions of polyunsaturated and monounsaturated fatty acids varying between seasons. In the laboratory, snails were exposed to one of three feeding scenarios over a 7‐day period (nil, low and high food) and changes in physiological condition (i.e., protein, lipid, carbohydrate content and malondialdehyde levels) were evaluated. Short‐term food limitation resulted in a marginally significant decrease in protein and increase in wet weight for snails on a high food diet, when compared to other treatments. When compared to baseline data, lipid content significantly decreased across all treatments, while protein and water content in the nil and low food treatments and wet weight in the high food treatment increased significantly. Malondialdehyde levels were lower in the nil and low food treatments, while increasing in snails fed the high food diet, indicating a higher metabolic response in well‐fed snails. These results suggest that alternative management strategies, such as adjusting grazing density and providing supplemental feed, may be required to prevent starvation and maintain treatment efficiency during periods of poor food availability.

Two Contributions to the Hypogeous Boletales of China: A Novel Rhizopogon Species and a New National Record of Turmalinea persicina - Jia Li; Chang Xu; Tai‐Jie Yu; Wen‐Hao Zhang; Xiu‐Juan Li; Yu‐Xian Gao; Yuan‐Tian Lu; Li‐Ping Tang (New Zealand Journal of Botany, 2026)
Hypogeous Boletales are ectomycorrhizal fungi with sequestered hymenophores; some species are ecologically valuable as edible mushrooms. Despite their ecological and economical importance, the diversity of this group in China remains poorly understood. In this study, we performed phylogenetic analyses based on four loci (ITS, LSU, TEF1‐α , and RPB2 ) and detailed morphological examinations of specimens belonging to Rhizopogon (Rhizopogonaceae) and Turmalinea (Boletaceae). We describe and illustrate R. sinoevadens , a new species from China, and report the first Chinese record of T. persicina , a species originally described from Japan. These discoveries underscore the previously underestimated diversity of hypogeous Boletales in China and provide a foundation for future taxonomic and ecological studies.

Taxonomy and Phylogeny of Fomitiporia bharatavarsa , an Undescribed Species From Tamil Nadu, Southern India - Elangovan Arumugam; Malarvizhi Kaliyaperumal (New Zealand Journal of Botany, 2026)
A new species of Fomitiporia is illustrated and described based on taxonomic studies and phylogenetic analyses. Fomitiporia bharatavarsa is characterized by perennial, resupinate basidiomes, circular pores (4–7 per mm), dimitic hyphal system, presence of hymenial setae, cystidioles, abundant rhomboid crystals, and thick‐walled broadly ellipsoid‐to‐subglobose basidiospores measuring 5.5–6.3 × 5.2–5.5 µm. Phylogenetic analyses inferred from ITS and nLSU rDNA sequences revealed that F. bharatavarsa represents a new lineage and formed a sister group to F. aethiopica , F. carpinea , F. erecta , F. mediterranea , F. pseudopunctata , F. punicata , and F. tsitsikamensis . Our study represents pioneering report on the new species of Fomitiporia , which has been described and discussed with allied taxa in taxonomic and phylogenetic aspects.

Revealing Coprophilous Basidiomycetes in Sri Lanka: An Integrative Taxonomic Assessment of Dung‐Inhabiting Mushrooms - Nethmi M. Perera; Thivanka M. Peiris; Helani H. Munasinghe; Mayuri Munasinghe; Isuru Sakbo Uyangoda; Milan C. Samarakoon; Danushka S. Tennakoon; Buddhika P. Dharmasena; Samantha C. Karunarathna; Kasun M. Thambugala (New Zealand Journal of Botany, 2026)
Coprophilous fungi inhabit animal dung and play a crucial role in ecological balance by decomposing animal waste and serving as a food source for coprophagous and mycophagous arthropods. This study aimed to systematically characterize the diversity of coprophilous basidiomycetes across selected regions of Sri Lanka, and it characterized seven coprophilous basidiomycete specimens representing five distinct species from selected sites in Sri Lanka using both morphological and molecular methods. Specimens associated with elephant dung and horse manure were obtained from the Colombo, Gampaha, Nuwara Eliya, and Ratnapura districts. Taxonomical identification was achieved via integrated macro‐ and micromorphological analyses. Morphological characterization relied on detailed macro and micromorphological observations, while phylogenetic relationships were inferred from combined ITS and nLSU sequence data analyzed using maximum likelihood and Bayesian methods. Five species were identified and described at the species level, representing the first documented records of these taxa in Sri Lanka. These species include Conocybe volvata , Coprinopsis cinerea , Narcissea cordispora , Panaeolus antillarum , and Panaeolus cyanescens . The findings enhance the documentation of coprophilous fungal diversity in Sri Lanka and establish a foundation for future ecological and biotechnological research on dung‐inhabiting fungi in tropical ecosystems.

Wild Edible Morels in Uzbekistan: Ethnomycological Knowledge and Seasonal Use Across Wooded and Dryland Habitats - Yusufjon Gafforov (New Zealand Journal of Botany, 2026)
Wild edible morels are among the most recognisable spring fungi in Uzbekistan, yet their species‐level identity, locality‐based distribution and ethnomycological significance remain incompletely documented. This review synthesises evidence concerning Morchella esculenta (L.) Pers. and Morchella steppicola Zerova by integrating diagnostic morphology, vernacular recognition, seasonal gathering, habitat associations, household preparation, preservation, culinary use, historical sources and locality‐based Global Biodiversity Information Facility occurrence data. Uzbekistan‐specific literature forms the primary evidence base, while Central Asian and broader Eurasian studies provide comparative and interpretive context. The evidence indicates that both species are recognised as edible spring fungi, but their documentation is markedly uneven. Morchella esculenta is more extensively recorded in relation to local names, morphology, habitat, drying, rehydration and culinary use, whereas M. steppicola has a narrower published profile but is particularly associated with steppe, semi‐desert and other open dryland habitats. The reviewed dataset contained 21 accepted records of M. esculenta , of which 16 georeferenced records represented nine mapped localities across four countries and nine accepted georeferenced records of M. steppicola representing nine mapped localities in Kazakhstan and Uzbekistan. These records support broad ecological differences between the species but remain too sparse and geographically uneven to define complete distributions, abundance, population trends or conservation status. Historical and comparative sources indicate a longer regional documentary background, including medieval materia medica references and Soviet‐period records, but do not demonstrate continuity with contemporary household, market, medicinal or cultural practices in Uzbekistan. Wild edible morels are therefore best interpreted as seasonal biocultural food resources supported by an incomplete evidence base. Future research should prioritise field‐based ethnomycology, voucher‐supported identification, georeferenced occurrence records, multi‐season ecological monitoring, market assessment and documentation of knowledge transmission before cultivation or value chain development is pursued.

Checklist of Orchidaceae From Brazilian Amazon Restingas - Deivid Lucas de Lima da Costa; Felipe Fajardo Villela Antolin Barberena (New Zealand Journal of Botany, 2026)
In Brazil, restingas (coastal sandbank vegetation) are distributed along the coast in the Atlantic Forest, Caatinga, Cerrado, and Amazon phytogeographic domains. Orchidaceae is one of the botanical families with the greatest species richness in restingas in the Atlantic Forest but has been poorly documented in Amazonian restingas , resulting in limited knowledge in these environments. Thus, the aim of this study was to present a checklist of Orchidaceae from Brazilian Amazon restingas . We consulted herbaria, reviewed the literature, and carried out field collections on the coast of the Salgado microregion in the state of Pará. Twelve genera and 20 species of Orchidaceae were found. Two species are endemic to Brazil, and nine are new records for the study area. Orchidaceae occur in four phytophysiognomies: restinga forest (10 species, five exclusive), open thicket formation (8 spp.), dune field (7 spp., three exclusive), and herbaceous marsh (2 spp.). Eleven species were exclusively terrestrial, six exclusively epiphytes, two epiphytes and terrestrial, and one species was a nomadic climber. Future studies should investigate the ecological relationships between epiphytic orchids and their phorophytes in Amazonian restingas because these relationships have shown to be fundamental in restingas in the Atlantic Forest.

Small sample sizes dominate recent acoustic telemetry studies of fish movements and migrations - Dagmara Błońska; Ali Serhan Tarkan; J. Robert Britton (Journal of Fish Biology, 2026)
Acoustic telemetry (AT) tracks fish movements across time and space but is constrained by high costs, challenges in capturing fish and obtaining sufficient data. A meta‐analysis of AT studies completed between 2019 and 2023 extracted data on 584 records across 258 species. These revealed that 77% of AT studies tagged fewer than 100 individuals per species (median: 39), with 83% of tagged fish providing data used for movement analyses. These results suggest that AT studies can be limited in their ability to analyse fish movements and migrations at population levels.

Neotropical Snakes Reveal Different Geological Times for Dispersal Corridors Between Amazon and Atlantic Forests - Matheus Pontes‐Nogueira; Tiago F. Carrijo; Ricardo J. Sawaya (Zoologica Scripta, 2026)
Three forested dispersal corridors have been proposed within the diagonal of open/dry landscapes in South America and the relative importance of each one has been the subject of debate for forest organisms. We analysed the biogeographical history of three snake genera ( Bothrops , Philodryas , and Micrurus ) from different families (Viperidae, Dipsadidae, and Elapidae, respectively) to test the corridors' importance. We reconstructed the biogeographical history of the groups by Maximum Likelihood models and implemented Biogeographical Stochastic Mapping (BSM) to analyse the average number and the mean ages of dispersals through each corridor. The statistical significance of dispersal ages was tested via Wilcoxon‐Mann–Whitney tests. The Central corridors presented the highest average number of dispersals for all groups combined, as well as for Micrurus and Philodryas genera. However, the Eastern corridor was more important for the Bothrops genus. Most dispersals in the Western corridor are likely to have been older than the other two, prior to the Pliocene. Dispersals in the other corridors likely occurred mostly during the Pliocene. Our results do not support the hypothesis of terrestrial vertebrates dispersing mainly through the Western corridor. We reinforce the importance of incorporating the time dimension in biogeographical studies, as dispersal ages varied among the three corridors.

‘The most advanced outpost of cultivation’: palynological evidence for cereal agriculture and population resilience in a marginal upland environment - Helen Essell; Gill Plunkett (Journal of Quaternary Science, 2026)
Upland farming in Europe is frequently assumed to have been limited and precarious, despite relict spade‐dug ridges providing firm evidence of past crop growing. Direct evidence for crop types in post‑Medieval to Modern (~since 1500 CE) uplands is rare; yet, in Ireland, relict spade‐dug ridges that date to this period are commonly interpreted as potato beds, generally assumed to have been abandoned during the Great Irish Famine of 1845–1852 CE. This assumption has seldom been tested and reinforces narratives of upland marginality and climatic vulnerability. Here, we apply palynology to cultivation ridge soils in three relict field systems associated with disused cottages in the foothills of the Mourne Mountains, Northern Ireland. We find that cereals—not potatoes—were grown in these upland fields, extending the history of cereal growing in the Mournes from the mid‐12th until the 20th century CE. These results show that permanent occupation persisted through a period when uplands were abandoned elsewhere in Ireland, demonstrating the resilience of upland populations in what is widely regarded as a marginal environment. Our findings challenge entrenched assumptions about historic upland agriculture and highlight the importance of empirically testing the nature of past land use.

Discovery of Signature Metabolites as Potential Biomarkers for Anguillid Herpesvirus 1 ( AngHV ‐1) During Outbreak in Anguilla bicolor Glass Eel - Ekky Ilham Romadhona; Sutanti Sutanti; Handang Widantara; Yohanes Pamungkas Bawono; Annisa Fitri Larassagita; Betutu Senggagau; Edy Barkat Kholidin; Lili Sholichah; Indah Mastuti; Bunga Rante Tampangallo; Arief Taslihan; Sri Nuryati (Journal of Fish Diseases, 2026)
This study evaluated the metabolites of Anguilla bicolor during an outbreak of Anguilid Herpevirus 1 (AngHV‐1) disease. Two experimental groups, infected glass eels (P) and healthy glass eels (N), were established, with three biological replicates per group, each replicate comprising pooled samples from 10 glass eels (0.15 ± 0.03 g). Metabolomic analysis identified 212 compounds in the glass eel, including L‐palmitin, PC (18:1/0:0), choline, cinnamic acid, PC (16:1/0:0), creatine, monoolein, hypoxanthine, L‐histidine, oleostearic, L‐carnitine, linoleoyl, urocanic acid, arachidonic acid and taurocholic acid, which exhibited the 15 highest VIP scores. The infection with AngHV‐1 affected key pathways, including histidine metabolism, beta‐alanine metabolism, arginine biosynthesis and nicotinate and nicotinamide metabolism. Biomarker analysis revealed the downregulation of L‐phenylalanine, Stearidonic acid, 2‐Arachidonoyl glycerol, Acetyl‐L‐carnitine, carotenal and γ‐Guanidiobutyrate ( p A. bicolor glass eels.

Assessing the Role of Tropical Intraseasonal Oscillations in Occurring Extreme Rainfall Events Over Sri Lanka - Bibhuti Sharan Keshav; Akhilesh Kumar Mishra (International Journal of Climatology, 2026)
The weather and climate of the tropical region are significantly modulated by the tropical intraseasonal oscillations. These oscillations are mainly constituent of convectively coupled equatorial waves (CCEWs) and Madden–Julian oscillation (MJO). Though a smaller region and surrounded by oceanic water, the country Sri Lanka faces various types of extreme weather conditions. The extreme rainfall event (ERE) is one of the major disasters and the influence of these tropical waves in the occurrence of extreme events cannot be overlooked. The modulation of EREs by these oscillations is analysed over Sri Lanka during two core monsoon and two inter‐monsoon seasons using very high‐resolution 12 × 12 km rainfall from Indian Monsoon Data Assimilation and Analysis (IMDAA) reanalysis from 1979 to 2020. The probability of ERE is calculated during dry and wet phases of the different waves relative to the climatological probability for all the seasons. These probabilities are not consistent and highly varying across the seasons over Sri Lanka. The modulation of extreme rainfall by the MJO and CCEWs is clearly evident during wet and dry phases of the waves, with a systematic increase (decrease) in the probability of extreme events during convectively active (suppressed) conditions. The results revealed that the wet phase of the equatorial Rossby (ER) and mixed‐Rossby gravity and tropical depressions together (MT) waves during northeast monsoon (NEM) season show maximum increase in the probability of ERE up to 150% while their dry phases reduced the probability of ERE by 100% during first inter‐monsoon (FIM) season over eastern parts of the country. It is important to note that these probabilities are relative to the climatological values. The probability of ERE reduced (increased) during dry (wet) phases for MJO and Kelvin waves during southwest monsoon (SWM) over western regions with lesser quantity. However, MJO has increased the probability of ERE over eastern parts during NEM season. To assess the broader impact over the country, the probabilities are spatially averaged and it is observed that the maximum probability of ERE occurs in the wet phase of ER followed by MT wave during NEM season. The wave filtered anomalies of vertically integrated moisture flux convergence (MFC) linked to the wet phases of the waves play a major role in modulating the ERE over the region.

Residency and Space Use of Endangered Smoothhound Sharks ( Mustelus mustelus ) in Relation to Marine Protection and Demersal Longline Fishing Along South Africa's South Coast - Eugin Bornman; Taryn S. Murray; Neil Hammerschlag; Enrico Gennari (Fisheries Management and Ecology, 2026)
Shark populations are declining globally and the effectiveness of marine protected areas (MPAs) as a conservation tool may vary by species and environmental context. This study assessed space use and residency of smoothhound sharks ( Mustelus mustelus )—an endangered, yet highly exploited shark—in relation to spatial protection and fishing risk across three areas off the southern coast of South Africa. Passive acoustic telemetry data (2016–2023) from 37 individual sharks were analysed using residency indices and generalised additive models. Smoothhounds exhibited high site fidelity, with small daily home ranges ( 2 ). Residency showed a weak but significant negative relationship with fishing risk, indicating reduced residency in areas of higher fishing pressure. Residency was consistently higher within a MPA and adjacent bay waters, as compared to a nearby unprotected bay. These findings suggest that smoothhounds may respond to spatial protection and suggest that extending protection to the MPA‐adjacent high‐use areas could enhance conservation outcomes.

Emerging threat of avian influenza to the world's vultures - Jon Morant; Andrea Santangeli; Pablo Plaza; Sergio A. Lambertucci (Conservation Biology, 2026)

Risk reduction, rangeland use, and the future of human–carnivore coexistence - Craig Packer (Conservation Biology, 2026)
Efforts to reduce livestock losses to large carnivores are widely regarded as essential for promoting human–carnivore coexistence. Predator‐proof enclosures, compensation programs, improved livestock guarding, and real‐time predator alert systems can reduce depredation and retaliatory killing while enhancing pastoralist livelihoods. However, reducing livestock production risks may also alter livestock management decisions in ways that increase grazing pressure or reshape land‐use patterns. I applied insights from moral hazard theory, rebound effects, and common‐pool resource governance to examine how carnivore conflict mitigation interventions may influence pastoral land use and long‐term conservation outcomes. Reduced predation risk may encourage herd expansion, higher stocking densities, or spatial expansion into areas previously avoided because of carnivore presence. Although such responses may improve household resilience, they may also increase competition for forage with wild herbivores, intensify habitat degradation, or shift conflict spatially rather than eliminate it. Because durable coexistence requires accounting for the broader incentives created by successful risk reduction, I developed a framework integrating carnivore conflict mitigation with grazing management, ecological monitoring, and livelihood diversification.

Insect communities of late Pleistocene steppe–tundra and Holocene boreal forest ecosystems in central Yukon Territory, Canada - Scott L. Cocker; Svetlana Kuzmina; Nick Schafstall; Michael A. Monzon; Duane G. Froese (Journal of Quaternary Science, 2026)
Subfossil insect communities from the Quartz Creek site provide a detailed record of both Late Pleistocene steppe–tundra and Holocene boreal forest ecosystems in central Yukon Territory, Canada. Fifteen Pleistocene assemblages (marine isotope stages [MIS] 4 to 2) are dominated by steppe–tundra and dry‐tundra taxa, particularly the weevils Connatichela artemisiae and Lepidophorus lineaticollis , indicating a cold and dry environment with widespread Artemisia –grassland habitats. Periodic increases in mesic tundra, riparian and forest‐associated species reflect localised habitat mosaics within an otherwise arid landscape. Separated by a ~20 000‐year stratigraphic hiatus, the Holocene assemblages show a marked increase in taxa associated with shrubs, wetlands, and coniferous forests, including bark beetles such as Scolytus piceae , Polygraphus rufipennis, and Dendroctonus rufipennis , as well as the carpenter ant Camponotus herculeanus . These taxa indicate the presence of boreal forest habitats near the site by at least 6045 cal yr BP. Community composition and biodiversity indices show a clear difference between the Pleistocene and Holocene assemblages, reflecting a shift from relatively species‐poor steppe–tundra communities to more diverse assemblages associated with heterogeneous boreal forest environments. The continued absence of steppe–tundra specialists such as Connatichela artemisiae in our Holocene samples highlights the major restructuring of insect communities associated with the regional collapse of steppe–tundra ecosystems and the subsequent development of boreal forest environments in eastern Beringia.

Contrasting population genetic structures of freshwater eels ( Anguilla marmorata, A. bicolor, A. mossambica ) from Madagascar - Giada Speranza; Estelle Razafindranaivo; Denis Miranto Andriamahefa; Meelis Tambets; Marc Sztatecsny; Fanomezana Ratsoavina; Zafimahery Rakotomalala; Julia M. I. Barth; Michael Matschiner; Chrysoula Gubili; Robert Jehle; Robert Schabetsberger (Journal of Fish Biology, 2026)
Freshwater eels (genus Anguilla ) are of major biological and commercial interest due to their complex catadromous life cycle and as a high‐value fishery resource, but the biology of tropical species is still poorly understood. This study investigates the genetic integrity, diversity and population structure of three species of tropical eels ( Anguilla marmorata, A. bicolor and A. mossambica ) in the western Indian Ocean, based on partial nucleotide sequences of the mtDNA control region ( n = 107 samples) and the nuclear GTH2b gene ( n = 91 samples) for individuals collected from two freshwater systems in northern Madagascar. No first‐generation hybrids between the studied species were found, despite frequent heterozygosities at the nuclear locus. For the mtDNA control region, all species were characterized by high haplotype diversity (ranging between 0.992 and 0.996) and nucleotide diversity (ranging between 0.035 and 0.059), patterns that are consistent with a historical population expansion during the late Pleistocene as inferred from demographic modelling. In line with previous studies, we confirmed distinct mtDNA haplogroups in A. marmorata and A. bicolor which can be attributed to the partial and/or past separation of populations across the Indian Ocean, whereas the western Indian Ocean endemic A. mossambica revealed no structure. Our findings align with existing evidence for spawning areas in the western Indian Ocean for all three species, with A. marmorata partially separated from eastern Indian Ocean populations and A. bicolor showing higher connectivity. Our findings will aid in the future management of local anguillid stocks.

Physical Constraints on Future Tibetan Plateau Summer Precipitation: Emergent Relationships and Pareto Optimal Ensembles - Dongheng Li; Sixu Zhang; Xiaofan Lu; Guoxin Chen; Qiong Li; Suonam Kealdrup Tysa (International Journal of Climatology, 2026)
Precipitation projections over the Tibetan Plateau (TP) are critical for regional water resources adaptation and ecological security; however, inter‐model uncertainty substantially constrains their reliability. Based on the Phase 6 of the Coupled Model Intercomparison Project (CMIP6) multi‐model ensemble, this study employs emergent constraint schemes grounded in physical relationships and Pareto optimal ensemble selection schemes based on model screening, aiming to reduce uncertainties in mid‐to‐late 21st century (2051–2100) summer precipitation projections over the TP. The results indicate that inter‐model uncertainty is the dominant source limiting projection robustness, maintaining its leading role throughout the 21st century with a peak contribution during 2040–2050 and remaining significant in the mid‐to‐long term (69%). Emergent constraint relationships of TP summer precipitation with historical global warming trends and with Indo‐Pacific Warm Pool Sea Surface Temperature (SST) are both statistically significant and effectively reduce future projection uncertainty. Using Pareto optimal multi‐objective screening, bivariate constraint schemes pairing summer precipitation with the global warming trend and with Indo‐Pacific Warm Pool SST are found to outperform emergent constraints in compressing uncertainty. Specifically, they reduce uncertainty by more than 30% under the low emission scenario and can reach up to 40% under the medium and high emission scenarios. After constraint application, the projected mid‐to‐long term summer mean precipitation over the plateau converges to 5.77–7.22 mm day −1 , effectively correcting the systematic overestimation present in the original ensemble. Highly consistent spatial patterns across methods enhance projection robustness. Constrained increments show a south to north decreasing gradient, consistently suppressing southern overestimation. Most importantly, the optimal scheme reveals negative precipitation anomalies over the northwestern plateau, suggesting that this region may face a localised aridification risk.

Marine migration influences mercury accumulation in anadromous Arctic char ( Salvelinus alpinus ) - Isabel R. Hilgendag; Michael Power; Mehdi M. Aqdam; Christopher W. Lewis; Zoya Martin; Ashley D. Ehrman; Heidi K. Swanson (Journal of Fish Biology, 2026)
Mercury (Hg) is a globally distributed toxic metal present in northern natural environments that biomagnifies in food webs and bioaccumulates in apex predator fish, such as Arctic char ( Salvelinus alpinus )—an iteroparous species with a circumpolar distribution. Arctic char exhibit a variety of life history types, with the migrating, anadromous life‐history type supporting many subsistence and small‐scale commercial fisheries in the Arctic and sub‐Arctic. Despite anadromous Arctic char having generally lower Hg concentrations than non‐anadromous conspecifics, the mechanisms that contribute to significant inter‐individual differences within this life‐history group have not been well investigated. A total of 119 anadromous Arctic char were captured from inner Frobisher Bay on Baffin Island near Iqaluit, Nunavut, in 2018 and 2019, to investigate causes of inter‐individual differences in Hg concentrations in the anadromous life‐history type of Arctic char. As hypothesized, Hg concentrations significantly decreased with increasing marine prey reliance; marine prey reliance—quantified using δ 34 S ratios—explained 93% of the variability in Hg. Arctic char that relied more on marine (vs freshwater) prey had lower Hg concentrations. Delta 34 S ratios and average somatic growth rate (size‐at‐age) were the best predictors of Hg concentrations among the set of biological variables assessed, and both were negatively related to Hg concentrations in common age groups (i.e., ages 9–13). For samples that had migration data available, Hg concentration increased with age‐at‐first migration ( R 2 = 0.32) and decreased with number of marine migrations ( R 2 = 0.57), suggesting that plasticity in life history tactics affects Hg concentrations in anadromous Arctic char. Overall, results indicate that differences in habitat use and feeding environment (i.e., freshwater vs. marine) play a significant role in determining Hg bioaccumulation in anadromous Arctic char.

From Rare to Recurrent: Intensifying Hot–Dry Extremes Across Romania - Viorica Nagavciuc; Monica Ionita (International Journal of Climatology, 2026)
Using a novel high‐resolution monthly gridded observational dataset for Romania (i.e., 1901–2024; derived from 165 homogenised stations), we quantify the evolution of compound hot–dry months, defined as concurrent exceedances of a Standardised Temperature Index (STI ≥ +1) and deficits in the 1‐month Standardised Precipitation–Evapotranspiration Index (SPEI1 ≤ −1), in terms of frequency, spatial extent, and co‐occurrence probabilities. Late‐century projections are assessed using bias‐corrected EURO‐CORDEX regional climate simulations (RoCLIB dataset) under RCP4.5 and RCP8.5. Our results show a pronounced hydroclimatic transition toward more frequent and spatially extensive compound events, accelerating since the 1990s amid rising country‐mean temperatures and declining short‐term water‐balance anomalies. Persistent hotspots of joint probability emerge in the eastern Moldavian Plateau and southeastern lowlands (i.e., lower Danube–Bărăgan Plain–Black Sea coast), while elevated terrain exhibits relative buffering. Period‐wise comparisons (i.e., 1901–1931, 1932–1962, 1963–1993 and 1994–2024) reveal widespread increases in joint probability (typically 12%–20% across most of the country, with conditional heat–drought coupling (P(dry|hot)) strengthening across the eastern Carpathian foreland and Transylvanian Plateau but attenuating along the Lower Danube and coastal margins, indicating that amplified compound risk stems predominantly from the rising prevalence of hot months. The complementary conditional probability P(hot|dry) also rises across the southern and eastern lowlands, indicating that recent dry months are increasingly likely to be hot. Projections for 2071–2100 anticipate further intensification to 4–5 months yr. −1 (RCP4.5) up to 6–7 months yr. −1 (RCP8.5), with joint probabilities reaching 20%–35% and 35%–60%, respectively, rendering such conditions recurrent to near‐normative across key agricultural lowlands.

Origins and relationships of endemic Hawaiian sabre‐toothed blennies in the genus Plagiotremus (Blennioidei: Blenniidae) - Mykle L. Hoban; Cameron A. J. Walsh; Randall K. Kosaki; Brian W. Bowen (Journal of Fish Biology, 2026)
The sabre‐toothed blennies (tribe Nemophini) are renowned for vivid colouration and several evolutionary adaptations, including a venom that resembles opioids in both chemistry and function. The genus Plagiotremus contains 11 species distributed across the Indo‐Pacific and Red Sea, including two nominal species endemic to Hawai'i. Here, we use mitochondrial COI and cytb in addition to select morphological characters to examine the relationships of Hawaiian endemics to their widely distributed sister species, along with their phylogeography and evolutionary relationships above and below the species level. The Hawaiian endemic P. ewaensis was fully diverged from the widespread P. rhinorhynchos at COI (~4.5%), with genetic diversity patterns suggesting the possibility of a Hawaiian origin for the species pair. In contrast, the endemic P. goslinei was polyphyletic with the widespread P. tapeinosoma , sharing several haplotypes in both COI and cytb and indicating recent/ongoing contact and population‐level separation. The Marquesan population of P. tapeinosoma was morphologically and genetically distinct and ~1.7%–2.9% divergent from all other groups, and may warrant elevation to species. The P. goslinei / tapeinosoma group showed significant population differentiation across the Indo‐Pacific (COI Φ st = 0.786, p st = 0.801, p ewaensis / rhinorhynchos group showed low non‐significant differentiation (COI Φ st = 0.073, p = 0.06) with one frequent COI haplotype shared within P. rhinorhynchos across the Indo‐Pacific. Ancestral reconstruction analyses of P. goslinei / tapeinosoma / azaleus invoke the tantalizing possibility of an East Pacific origin for the species group. Our findings provide further support for biodiversity feedback in the Indo‐Pacific and show that endemic Hawaiian species with widely distributed sister taxa may have dramatically different evolutionary histories.

Taxonomic assessment of the glyptosternoid catfish Parachiloglanis hodgarti (Hora, 1923) based on morphometric analysis of type specimens and riverine populations in Nepal - Bhaba Amatya; Kumar Sapkota (Journal of Fish Biology, 2026)
This study addresses a major gap in knowledge regarding intraspecific morphological variation in Parachiloglanis hodgarti (Hora, 1923) (Sisoridae) by conducting comparative morphometric analyses of populations from Nepal's principal river drainages (Gandaki, Koshi and Karnali), the topotypic population from Pharping, and the holotype to evaluate the taxonomic implications of this variation. Eighteen size‐corrected morphometric traits were analysed in 108 specimens collected from Pharping ( n = 24), Gandaki ( n = 28), Koshi ( n = 28) and Karnali ( n = 28). Principal component analysis (PCA) and linear discriminant analysis (LDA) revealed pronounced population structuring, with the Karnali population showing the strongest multivariate differentiation. Variation among populations was primarily associated with body proportions, head morphology and fin morphology. Univariate analyses detected significant differences in individual morphometric traits among populations, with Pharping showing the highest number of significantly differentiated traits and Gandaki the fewest. Comparisons with the holotype revealed morphometric differences across all populations. Although the Karnali population differed from the holotype in the greatest number of traits (11), it differed from the Pharping topotypic population in only three traits. Because the Pharping topotypic population represents the closest extant proxy for the holotype and closely resembles it in overall morphometric characteristics, the greater divergence between Karnali and the holotype is likely attributable to preservation‐related deformation, historical and contemporary differences in measurement protocols, or both, rather than genuine taxonomic differentiation. Collectively, these findings demonstrate geographically structured morphological variation while supporting continuous intraspecific differentiation rather than discrete taxonomic separation. The morphological differentiation observed in the Karnali population may reflect localised evolutionary divergence associated with geographic isolation and environmental heterogeneity, although confirmation will require integrative molecular and ecological investigations. This study establishes a population‐level morphometric framework for P. hodgarti in Nepal and provides a baseline for future taxonomic, evolutionary and ecological research.

Drainage Water Recycling in Tile‐Drained Agricultural Landscapes: An Integrated Review of Hydrologic and Water Quality Performance, Co‐Benefits, Trade‐Offs and Research Gaps - Sina Kosari; Abdolmajid Liaghat; Khaled Ahmadaali; Bijan Nazari (Irrigation and Drainage, 2026)
Drainage water recycling (DWR) is an emerging practice in tile‐drained agricultural landscapes that stores tile drainage in reservoirs and reapplies it as supplemental irrigation, jointly targeting agronomic and environmental objectives. A systematic search identified 27 peer‐reviewed records examining DWR, including 11 field‐based studies (two of which were field‐modelling hybrid analyses), eight modelling studies, seven review/synthesis papers and one dataset paper. Reported outcomes include reductions in nitrate–nitrogen losses of up to 37% and reactive phosphorus of up to 39%, together with yield increases of up to 61% for maize and 31% for soybean in dry years. These concurrent benefits, reduced pollutant loads, more reliable on‐farm irrigation supplies and improved crop yield distinguish DWR from most other edge‐of‐field practices. DWR systems may also provide aquatic and wetland habitats, attenuate runoff and generate aesthetic and recreational co‐benefits, especially when integrated with constructed wetlands or other best management practices. However, land requirements, potential salinity build‐up and microbial contamination in reservoirs, and uncertain net greenhouse gas balances highlight the need for careful design, adaptive operation and monitoring. A pronounced lack of independent long‐term field data on water quality, phosphorus dynamics, surface runoff, habitat services and greenhouse gas emissions remains a critical research bottleneck.

Long‐Term Changes in the Relative Contribution of Mediterranean Cyclones and Sudanese Lows to Precipitation Over Iraq (1954–2023) - Qusay Kazim Aliwi Bandar; Khamis Daham Muslih (International Journal of Climatology, 2026)
Precipitation variability in Iraq is commonly evaluated through annual trend analysis; yet the synoptic systems driving this variability remain poorly examined. This study examines the long‐term spatial and temporal trends in the frequency and precipitation contributions of Mediterranean cyclone days and Sudanese low days over Iraq during the period 1954–2023, with both systems identified based on NCEP/NCAR reanalysis data. Using the Mann–Kendall test and Sen's slope estimator, the results reveal a significant decrease in the frequency and precipitation contributions of Mediterranean cyclone days over all parts of Iraq. Conversely, Sudanese low days show increasing frequency and growing precipitation contributions. However, this shift did not compensate for the reduction in precipitation efficiency associated with Mediterranean cyclones, resulting in an overall decline in total precipitation. These results demonstrate a structural reorganization of synoptic drivers across Iraq's transitional climate zone, with implications for drought risk and water resource management across Iraq and other parts of the Middle East.

Climate Change Intensifies Cropland Drought Exposure in the Indus River Basin During the 21st Century - Muhammad Asad Hussain; Barira Haider; Muhammad Waseem; Buda Su; Muhammad Akbar; Jinlong Huang; Jian Zhou; Tong Jiang (International Journal of Climatology, 2026)
Drought poses a significant threat to agriculture in the transboundary Indus River Basin (IRB), which supports over 300 million people through direct and indirect dependence on agriculture. With limited cropland and growing climatic stress, the basin faces an increasing risk to food security. Yet, comprehensive assessments of cropland exposure to drought under a changing climate and socioeconomic conditions remain lacking. This study evaluates present and future cropland exposure to drought across the IRB using cropland data from the Land‐Use Harmonisation dataset (LUH2) and bias‐corrected output from seven CMIP6 global climate models, validated against ERA5 reanalysis data. We examined a baseline period (1995–2014) and three future time slices (2021–2040, 2041–2060 and 2081–2100) under seven Shared Socioeconomic Pathways (SSP1‐1.9 to SSP5‐8.5). Drought characteristics are quantified using the Standard Precipitation Evapotranspiration Index (SPEI) combined with run theory, incorporating CO 2 emissions. Results indicate that drought frequency is increasing in the future across the emission scenarios relative to the baseline. Cropland exposure displays pronounced spatial heterogeneity and a clear dynamic evolution over time, with the highest concentrations in the central IRB, particularly the Indo‐Pak Punjab and riparian corridors. By 2081–2100, annual cumulative exposed cropland area expands from 1875.3 to 2886.5 km 2 , representing an increase of 71.8%–88.1% relative to the baseline. Furthermore, attribution analysis shows that climate change dominates the increase in exposure through 2060, whereas cropland emerges as the primary driver by 2081–2100. These findings underscore the need for dual‐track drought risk‐management: climate‐focused adaptation for near‐term and integrated land‐use planning for long‐term resilience to safeguard food security in the IRB.

Synergistic Effects of the Westerly and Asian Monsoon on Summer Rainfall in the Tarim Basin of Northwest China Under Different Climate Backgrounds - Lixia Meng; Qiang Zhang; Shujuan Hu (International Journal of Climatology, 2026)
Based on the Japanese 55‐year Reanalysis (JRA‐55) atmospheric circulation data provided by the Japan Meteorological Agency and monthly rainfall data from 28 meteorological stations across the Tarim Basin in Northwest China extracted by the China Meteorological Data Network from 1961 to 2022, the synergistic effects of the westerly and Asian monsoon on summer rainfall in the Tarim Basin are investigated. Results show that summer rainfall in the Tarim Basin has experienced a significant interdecadal increase over the past several decades and can be divided into two periods: A dry period (1961–1987) and a wet period (1988–2022). Under different climate backgrounds, the atmospheric circulations associated with the summer rainfall anomaly show obvious differences. The westerly indicated by the Silk Road Pattern (SRP) correlates well with the summer rainfall in the two periods, but the South Asian summer monsoon (SASM) (East Asian summer monsoon, EASM) is only well related to the summer rainfall in the dry period (wet period). In the dry period, the strengthened SRP and weakened SASM are associated with the southward movement of the subtropical westerly jet (SWJ) over Central Asia (CA). Meanwhile, the anomalous cyclone over CA and the anomalous anticyclone over the Arabian Sea strengthen the transport of water vapour from the Arabian Sea to the Tarim Basin. So, the Tarim Basin receives more summer rainfall. During the wet period, the strengthened SRP and weakened EASM as represented by the strengthened EAP atmospheric teleconnection can result in the SWJ moving northward over East Asia. Meanwhile, in conjunction with an anomalous anticyclone over the Mongolian Plateau, the westward extension of the West Pacific Subtropical High enhances the transport of water vapour from the Bay of Bengal to the basin. As a result, the Tarim Basin generates more summer rainfall.

A New Hydroclimatic Signature: Negative NAO Dominance Under Weak La Niña Conditions During the 2025–2026 Northwest Africa Floods - Afshin Amiri; Silvio Jose Gumiere; Hossein Bonakdari (International Journal of Climatology, 2026)
The winter of 2025–2026 in Morocco exhibited a rapid hydroclimatic transition from prolonged drought to widespread flooding, representing an emerging hydroclimatic signature across Northwest Africa. Seasonal precipitation exceeded long‐term averages by 35.09%, triggering severe flash flooding in December 2025 and extensive riverine inundation across northern basins in February 2026. Analysis of large‐scale circulation from the ERA5‐Land reanalysis reveals a pronounced southward displacement of the North Atlantic jet stream, with core wind speeds exceeding 75 m s −1 at 250 hPa. Concurrent sea‐level pressure anomalies show a weakened Azores High (−11 hPa) and a relatively shallow Iceland Low (+8 hPa), indicating a negative phase of the North Atlantic Oscillation. Simultaneously, sea surface temperature anomalies in the Niño 3.4 region reached approximately −1°C, consistent with weak La Niña conditions. The coexistence of a negative NAO phase and weak La Niña conditions coincided with broader atmospheric circulation anomalies over the North Atlantic sector. However, statistical analyses indicate that NAO variability represented the dominant control on precipitation over Morocco. These circulation anomalies favoured repeated moisture‐rich Atlantic storms and atmospheric‐river–like transport towards Morocco. Satellite observations from Copernicus Sentinel 1 confirm extensive floodplain inundation along the lower Sebou River during peak flows. The results demonstrate that the negative phase of the North Atlantic Oscillation was the primary atmospheric driver of the 2025–2026 floods, while weak La Niña conditions represented a secondary background influence on the large‐scale circulation. Storm sequencing and orographic enhancement further amplified runoff generation and flood magnitude across Moroccan river basins.

Mortality in Salmon ( Salmo salar ) Fry Related to Lipoid Liver Disease Induced by Unbalanced Fatty Acid Composition of the Diet - Caroline Ek; Lo Persson; Charlotte Axén (Journal of Fish Diseases, 2026)
In 2023, all but one Swedish restocking farm rearing Baltic salmon and sea trout fry experienced massive mortality caused by lipoid liver disease (LLD). The struck farms used the same feed, and this was suspected to be the cause of the outbreak. We performed two parallel feed trials in three salmon populations as well as fatty acid and antioxidant analyses of feed and fish to investigate the causal relationship between the feed and the LLD mortality. Significant mortality was induced in one population and LLD histopathology was induced in all three populations in groups fed the suspected feed (test feed) but not in the control groups, linking the test feed to the outbreak in 2023. Fatty acid analysis revealed a difference in bound fatty acid composition between the suspected feed and the control feeds, including higher amounts of erucic acid. Erucic acid has negative health effects for fish by altering lipid metabolism. It is present in for example, capelin, a main ingredient in this feed. The test feed also contained lower levels of several antioxidants, especially vitamin A. Antioxidative status of the fish could not be fully analysed but results indicated a difference in antioxidative status between the populations.

Continuous darkness is associated with improved growth performance during a high‐temperature period and sex‐specific modulation of early gonadal development in juvenile yellowtail ( Seriola quinqueradiata ) - Yuya Hasegawa; Kiko Shibata; Taiga Abe; Takurou Hotta (Journal of Fish Biology, 2026)
Selective breeding of yellowtail ( Seriola quinqueradiata ) is expanding in Japan, increasing the demand for practical reproductive control tools in commercial aquaculture to reduce genetic risks from escapees. Slowing early gonadal development through environmental manipulation may support future sterilization strategies, particularly when combined with other techniques. This study aimed to examine somatic growth and early gonadal development in juvenile yellowtail reared under continuous darkness (0L:24D). Juveniles were reared under 0L:24D or a 12L:12D photoperiod (control) and sampled at Weeks 0, 2, 4, 6, 8 and 10. Growth was recorded at each time point, and gonads were examined by histology and immunohistochemistry to assess gonadal sex differentiation, germ‐cell proliferation and onset of meiosis. Water temperature increased similarly in both groups and exceeded 28°C from Week 6 onward. Despite identical feeding rations, fish reared under 0L:24D were significantly larger at Weeks 8 and 10 than controls. Gonadal sex differentiation progressed normally in both groups, and germ‐cell proliferative activity did not differ between groups. SYCP3‐positive germ cells were not detected at Week 6 under 0L:24D, whereas the proportion of SYCP3‐positive germ cells at Weeks 8 to 10 was comparable to that in controls, suggesting a possible transient difference in the initial appearance of SYCP3‐positive germ cells. In females, fish reared under 0L:24D showed lower area fraction and diameter of chromatin nucleolus‐ and perinucleolus‐stage (CN/PN) oocytes at Weeks 8 and 10, suggesting reduced development of CN/PN‐stage oocytes. These results suggest that, under the present single‐tank experimental conditions, rearing under continuous darkness was associated with improved growth performance during the high‐temperature period and sex‐specific changes in early gonadal development in juvenile yellowtail.

Morphological Traits, Phenological Development and Water Productivity of Yaghouti Grapevine Under Stage‐Specific Deficit Irrigation in a Hyperarid Environment - M. Fazeli Rostampour (Irrigation and Drainage, 2026)
Efficient irrigation management is essential for sustainable viticulture in hyperarid regions. This 3‐year study (2022–2024) in south‐eastern Iran employed a strip–split plot design to evaluate three irrigation regimes—full irrigation, moderate deficit (50% soil moisture depletion) and severe deficit (70% depletion)—across four critical phenological stages. Climatic variability, ranging from a mild 2023 season to extreme thermal shocks in 2024, significantly influenced absolute physiological traits. Despite these interannual fluctuations, irrigation regimes consistently modulated leaf architecture and water productivity (WP). Specifically, deficit irrigation applied between veraison and harvest enhanced WP by 19%–44% (moderate) and 11%–20% (severe) compared with full irrigation. These gains were closely coupled with adaptive morphological plasticity; moderate stress induced strategic reductions in leaf area index and specific leaf area, effectively minimising canopy transpiration without compromising yield. The findings further revealed that supraoptimal temperatures (> 40°C) necessitated these physiological adjustments, whereas severe water stress during early spring thermal peaks or late‐winter cold shocks induced detrimental declines in leaf development. Overall, targeted moderate deficit irrigation during late‐season stages represents a robust strategy for enhancing WP while maintaining canopy integrity under volatile climatic conditions.

Intercomparison of a Regional Climate Model Ensemble for Selected European Catchments - Jane Leonor Roque; Francis Da Silva Lopes; Julian Alberto Giles; Benjamin D. Gutknecht; Bernd Schalge; Yikui Zhang; Marco Ferro; Petra Friederichs; Klaus Goergen; Stefan Poll; Arianna Valmassoi (International Journal of Climatology, 2026)
Understanding regional hydroclimatic variability and its drivers is essential to anticipate the impacts of climate change on water resources and sustainability. Yet, considerable uncertainty remains in the simulation of the coupled land–atmosphere water and energy cycles, largely due to structural model limitations, simplified process representations, and insufficient spatial resolution. Within the framework of the Collaborative Research Centre 1502 (CRC1502), this study presents a coordinated intercomparison of regional climate model simulations designed for water cycle process analysis over Europe. We analyse the performance of simulations using the ICON and TSMP1 model systems and covering the period 1990–2020, comparing against reference datasets (E‐OBS, GPCC, and GLEAM). We focus on 2‐m air temperature, precipitation and evapotranspiration over four representative basins—the Ebro, Po, Rhine, and Tisa—within the EURO‐CORDEX domain. Our analysis reveals systematic cold biases throughout most of Europe, with ICON generally outperforming TSMP1. ICON simulations exhibit heterogeneous performance in precipitation biases, with less overestimation than TSMP1, but still reflecting the persistent challenge of accurately simulating precipitation. TSMP1 and ICON generally agree on positive ET biases in southern and western Europe and negative biases in the north and east, with TSMP1 showing greater local differences than ICON. Sensitivity experiments using higher‐resolution sea surface temperature forcing data produced comparable performance among themselves; however, they outperformed the other models in simulating precipitation over the Ebro and Rhine basins across most seasons. ICON simulations at 3 km resolution further indicate that the inclusion of irrigation improves the representation of summer temperature and precipitation in the Po basin. This baseline evaluation provides a first assessment of the CRC1502's multi‐model ensemble and highlights key structural differences that influence model behaviour across hydroclimatic regimes.

Atmospheric Blocking Pattern as the Primary Driver of Subseasonal Greenland Ice Sheet Summer Melt Variability - Ruiwei Guo; Yao Yao; Dehai Luo; Jiaqi Shi; Lijuan Hua; Ruonan Zhang; Hejing Wang (International Journal of Climatology, 2026)
The anomalous summer melting of the Greenland Ice Sheet (GrIS) is one of the key signals of ongoing climate system changes. The complex spatiotemporal characteristics of GrIS and its impacts on global sea‐level rise have attracted increasing attention. Although previous studies have suggested that atmospheric blocking circulation can drive extreme melting events, the quantitative influence of subseasonal‐scale atmospheric processes on the total summer melt remains poorly understood. Based on a scale‐separation approach combined with Modèle Atmosphérique Regionale (MAR) simulations and satellite observations, this study provides the first systematic quantitative assessment of the contribution of subseasonal circulation processes to summer melting of the GrIS. While subseasonal processes account for an average of ~20% of the total summer melt, we find that a single pattern—Greenland Blocking (GB)—dominates this contribution. GB alone is responsible for up to 47% of the subseasonal melt, equating to approximately 10% of the total summer melt. The remaining subseasonal variance is driven by a spectrum of other circulation modes. To unravel the remaining subseasonal signal, we employ K‐means clustering to identify four distinct non‐blocking circulation patterns. However, their individual contributions are substantially smaller than that of GB. This study reframes the understanding of summer GrIS melt by highlighting the overwhelming dominance of blocking within the subseasonal framework.

Climate Transitions in the Argentine Pampas Exceed Global Rates and Reshape Crop Exposure: A Multi‐Period Köppen–Geiger Analysis (1901–2020) - Andrea Soledad Brendel (International Journal of Climatology, 2026)
Climate change is driving shifts in the spatial distribution of climate zones worldwide, with particularly strong impacts in mid‐latitude regions. The Argentine Pampas, one of the world's most important agro‐productive areas, provides a key case for assessing these dynamics. This study analyses Köppen–Geiger climate transitions across four consecutive 30‐year periods (1901–1930, 1931–1960, 1961–1990 and 1991–2020) using high‐resolution maps and a pixel‐by‐pixel approach. Transitions were classified into nine categories, distinguishing single‐driver processes—changes in aridity, summer temperature or precipitation seasonality alone—from compound transitions in which precipitation seasonality and summer temperature shifted simultaneously within the same pixel. Results reveal that climate transitions affected between 8.6% and 14.3% of the regional area across consecutive periods, consistently exceeding global averages. The temporal trajectory is non‐linear, characterised by successive reversals in the dominant process: early 20th‐century aridity increase, mid‐century aridity reduction with the retreat of semi‐arid conditions and a recent dominance of winter drought development. Compound transitions remained spatially marginal in every period (0.5% or less), indicating that hydroclimatic and thermal shifts generally operated as spatially distinct processes across the region. In the most recent period (1961–1990 to 1991–2020), transitions affected 11.6% of the Pampas, with winter drought development accounting for over two‐thirds of all changes, primarily through shifts from Cfa to Cwa climates—a pure single‐driver hydroclimatic transition. Crop exposure analysis indicates that more than 3.1 million hectares of cropland fall within transition zones, with 91% concentrated in the winter drought development belt, encompassing the core soybean–maize–wheat production system. These results demonstrate that climate change in the Pampas is expressed primarily as a reorganisation of hydroclimatic regimes and precipitation seasonality rather than as uniform trends in annual conditions. The identified transition rates and spatial patterns position the region as a mid‐latitude climate change hotspot and highlight the need for territorially differentiated adaptation strategies in highly productive agricultural systems.

Event‐Based Detection and Attribution‐Oriented Diagnosis of Compound Hot–Drought Extremes in a Typical Region of Central North China - Haiyan Zhao; Siyan Dong; Xinlei Zhang; Hao Wu; Zhenyu Han (International Journal of Climatology, 2026)
Compound hot–drought events are high‐impact extremes that can amplify agricultural, ecological, and socioeconomic risks, yet their event‐scale detection and attribution‐oriented diagnosis remain limited for inland transitional regions. Here, we use Shanxi Province as a representative case of Central North China and develop a daily event‐based framework to identify warm‐season compound hot–drought events during 1961–2023 by combining the Meteorological Drought Composite Index with concurrent exceedances of daily maximum and minimum temperature thresholds. We further detect long‐term changes and abrupt shifts, identify major event years, verify representative events using disaster‐impact records, and diagnose associated circulation pathways through causal effect network analysis. The results show that both the annual number of compound hot–drought event days and the annual compound‐event percentage increased significantly during 1961–2023, with an abrupt shift around 1996–1997. Most top‐ranked event years occurred after this transition, indicating intensified compound hot–drought risk in recent decades. Event‐scale analyses identify 1997, 2001, and 2019 as representative major events, whose temporal evolution and spatial extent are consistent with documented drought impacts. Spatially, increasing trends are observed at most stations, and their consistency with hot‐day trends is much stronger than with drought‐day trends, suggesting a heat‐dominated intensification pathway. Causal effect network analysis reveals significant links between Shanxi compound hot–drought variability and the British–Baikal Corridor (BBC) and Silk Road Pattern (SRP) wave trains. Their coupled influence favours persistent anticyclonic anomalies, suppressed convection, and reduced precipitation over North China, providing a physically interpretable circulation pathway for major events. These findings establish an observational–impact–circulation evidence chain for attribution‐oriented diagnosis and provide a basis for future formal attribution and early warning of regional compound extremes.

Impact of Surveillance and Depopulation Strategies on Fish Disease Transmission Among Net‐Cage Farms Near the Tongyeong Coast Based on a Spatiotemporal Hybrid Approach - Gyoungsik Kang; Ju‐sung Kim; Kyung‐Ho Kim; HyeongJin Roh (Journal of Fish Diseases, 2026)
Infectious diseases among fish farms present significant challenges to fish health and production. Horizontal transmission serves as one of the main mechanisms driving outbreaks in these settings. The dynamics of horizontal transmission are influenced by pathogen properties, host characteristics and environmental factors. Additionally, the implementation of epidemiological interventions can further shape the patterns and consequences of infectious disease spread. However, there is a paucity of studies assessing how specific epidemiological measures, such as timely disease surveillance and strategic depopulation, influence transmission and outbreak outcomes. This study utilized a spatiotemporal hybrid model to assess pathogen dissemination following an infectious disease event in Tongyeong, a prominent area for floating net cage aquaculture in Korea. We investigated how variations in sampling intensity affected the timing of disease detection and analysed the impact of two control strategies (immediate culling upon detection versus no culling) on the progression of disease and fish mortality. Findings revealed significant differences in disease detection timing and probability based on the surveillance sampling size. Early detection of disease was achieved when 100 fish were sampled, as opposed to a delayed response when only 5 fish were tested. Furthermore, the conditions under which surveillance occurred had a notable impact on both the spatial spread and the success of depopulation measures. Generally, prompt detection followed by immediate depopulation led to a decrease in disease‐related mortality over a wider area. However, this method also necessitated culling a substantially greater number of fish. Although the impact of these interventions may be influenced by geographical and environmental variables, our results suggest that the utility of depopulation strategies is closely linked to the efficacy of surveillance efforts and the epidemiological profile of the infection, such as its associated mortality rate and transmissibility.

The characteristics and expression profile of follicle‐stimulating hormone and luteinizing hormone during gonadal development in silver pomfret - Chunyang Guo; Dingyuan Zhang; Yi Wang; Xubo Wang; Shanliang Xu; Danli Wang (Journal of Fish Biology, 2026)
The hypothalamic–pituitary‐gonadal (HPG) axis, particularly follicle‐stimulating hormone (Fsh) and luteinizing hormone (Lh), is essential for the regulation of teleost reproduction. However, their expression dynamics and receptor distribution during gonadal development in silver pomfret remain poorly understood. This study aimed to characterize the expression profiles and cellular localization of Fshβ, Lhβ and their receptors (Fshr and Lhr) in the pituitary and gonads and to evaluate their potential roles in reproductive regulation. The different staining method and transmission electron microscopy (TEM) were used to analyse the structural changes of the pituitary gland during the reproductive season. Quantitative PCR (qPCR) and immunohistochemical (IHC) were used to detect the expression pattern of Fshβ and Lhβ. The results showed that the number of endocrine granules significantly increased before the reproductive season, and their electron density intensified. During the spawning season, the secretory granules gradually depleted, leading to the appearance of vacuolization. In the pituitary gland, the expression of fshβ in Stage IV was significantly higher in the female pituitary, but significantly higher in Stage V in the male. Fshβ and Lhβ signals were mainly located in the proximal pars distalis (PPD) and pars intermedia (PI) regions of the pituitary. In the gonad, Fshr signals were observed in the spermatogonia type A cells and Sertoli cells in testes, whereas Lhr signals were observed in spermatogonia and secondary spermatocytes in the testes. Fshr and Lhr signals were both observed in the follicle cells surrounding the oogonia and vitellogenic oocytes in the ovary of silver pomfret. The expression patterns of fshβ and fshr were essentially similar after different hormone treatments in the gonad and methyltestosterone (MT) could influence the expression of fshβ , lhβ and fshr in the testis. Taken together, our data suggest that Fshβ and Lhβ promote the development and maturation in the gonad, and Fshr and Lhr may be involved in ovary maturation and spawning.

Is a Commensal Here, a Pathogen There? Genotype Specific Responses by the Sea Anemone Nematostella vectensis to Vibrio Species - Justin Clark; Quinton Krueger; Tyler J. Carrier; Yehu Moran; Adam M. Reitzel (Molecular Ecology, 2026)
Animals rely on diverse molecular mechanisms to maintain beneficial microbial associations while also defending against pathogens, yet the extent to which these responses vary among genotypes of a single species remains poorly understood. Using individuals from different locations of the sea anemone Nematostella vectensis , we compared transcriptional responses to a commensal ( Vibrio diabolicus ) and pathogen ( Vibrio coralliilyticus ) bacterium. We find striking genotype‐specific divergence: individuals from Nova Scotia mounted a strong transcriptional response to V. diabolicus , whereas the North Carolina and Florida individuals showed almost no response to this same bacterium. In contrast, all individuals regardless of location exhibited a large transcriptional response to the pathogen V. coralliilyticus . These responses involved key immune pathways (e.g., cGAS‐STING, NF‐κB, and proteostasis‐related stress responses), suggesting that different genotypes deploy distinct molecular responses when encountering the same bacterium. The robust, immune‐like response of the individuals from Nova Scotia to a bacterium considered commensal in other populations indicates that V. diabolicus may not function as a commensal across the species range. Such genotype‐by‐microbe specificity points to potential local adaptation to particular bacterial partners that underscores the complexity of holobiont regulation across heterogeneous environments and stresses the importance of assessing additive, synergistic, and antagonistic interactions across hologenomic mosaics.

Phylogenomics of Musa acuminata subsp. banksii Elucidates Its Biogeographic History in New Guinea and Ancient, Natural Dispersal to Australia - Sander de Backer; Yves Bawin; Arne Mertens; Janet Paofa; Gou Rauka; John E. Thomas; Kathleen S. Crew; Andrew D. W. Geering; Bart Panis; Sebastien Carpentier; Julie Sardos; Steven B. Janssens (Journal of Biogeography, 2026)
Aim We aim to reconstruct the phylogeographical history of Musa acuminata subsp. banksii across New Guinea and Australia and to test whether its occurrence in Australia results from ancient natural dispersal or recent human‐mediated translocation. Location New Guinea and northern Australia (Sahul Shelf). Taxon M. acuminata subsp. banksii (F.Muell.) N.W.Simmonds (Musaceae). Methods We generated genome‐wide single nucleotide polymorphism (SNP) data using DArTseq for samples spanning the subspecies' range. Phylogenomic relationships were inferred using maximum‐likelihood locus trees and quartet‐based species‐tree inference. Divergence times were estimated with time‐calibrated analyses in BEAST, and spatial diffusion and lineage dispersal were reconstructed using continuous phylogeographical modelling (SERAPHIM). Results Our analyses place the ancestral area of M. acuminata subsp. banksii in the Bird's Head Peninsula approximately 4 million years ago (mya), consistent with the recent emergence of New Guinea. The Central Range of New Guinea likely acted as a major biogeographical barrier and channeled expansion through southern lowland corridors. Australian populations form a deeply divergent lineage that colonised the continent via the Torres Strait land bridge during the early Pleistocene. This colonisation event predates human arrival in the region by more than 2 million years. Main Conclusions The presence of M. acuminata subsp. banksii in Australia reflects ancient natural dispersal rather than human translocation. Australian populations represent a vicariant lineage with a distinct evolutionary history, highlighting northern Australia as an overlooked reservoir of wild banana genetic diversity. Our study illustrates how integrating phylogenomics, molecular dating, and spatial diffusion modelling can resolve long‐standing biogeographical questions in regions shaped by dynamic geological and climatic processes.

Natural Snow Accumulation Gradients Mediate Environmental and Plant Trait Responses to Earlier Snowmelt in Alpine Tundra - Jonathan J. Henn; Katherine Bardsley; Clifton P. Bueno de Mesquita; Sarah C. Elmendorf; Nancy C. Emery; Emily C. Farrer; Chiara Forrester; Jane G. Smith; Marko J. Spasojevic; Jennifer F. Morse; Katharine N. Suding (Global Change Biology, 2026)
Mountain ecosystems are experiencing rapid climate changes, with implications for biodiversity and ecosystem function. Changing snow dynamics, especially earlier melt, are influencing the timing and length of growing seasons, species phenology, and plant abundance. Because mountains are characterized by high topographical and microclimatic variation, effects of changing snow dynamics may depend on small‐scale variation in topographically mediated snow accumulation. Wind‐scoured areas frequently lack snow cover and thus may be less vulnerable to earlier snowmelt than areas of deep snow accumulation. Here, we test this expectation by applying black sand to accelerate snowmelt in five 400 m 2 plots arranged along hillslope gradients. We followed the effects of experimentally accelerated snowmelt on snow‐off timing, growing season length, soil moisture, and plant community composition for 6 years. The largest changes in snow‐off timing (average of 15 days earlier) and growing season length occurred in areas that accumulated the most snow, but there was no effect on soil moisture during the growing season. While plant community composition varied spatially along ambient gradients in snow depth, experimental early snowmelt caused only limited directional changes in composition through time. There was no evidence of homogenization of plant community composition across snow depth gradients. However, species climate niche traits (range in climatic water deficit and range in snow affinity) and specific leaf area explained some variation in species responses to the treatments over time. Taken together, areas that accumulate the most snow are likely to be the most sensitive to changing snowmelt, driving changes in snow‐off timing and growing season length. While we did not detect taxonomic shifts in the plant community over the course of 6 years, some traits can explain variation in plant responses, showing that changing environmental conditions are shifting plant strategies.

Metagenomic Insights Into Red Sea Biodiversity Across the Web of Life - Elisa Laiolo; Christopher A. Hempel; Balegh A. Abukabbos; Omar I. Abunayyan; Intikhab Alam; Taiba Alamoudi; Wejdan A. Alkhaldi; Zuhair M. Almubarak; Hamad A. Alnashri; Afrah Alothman; Tareq H. Alqahtani; Khalid A. Alshaikh; et al. (Environmental Microbiology, 2026)
Earth's biodiversity is central to ecosystem health and resilience, providing essential functions and services. The Red Sea is a recognised marine biodiversity hotspot with high endemism and unique environmental conditions that support extensive but poorly resolved biodiversity. Here, we applied metagenomic analyses to sediment samples collected from coastal to deep‐sea environments during the Red Sea Decade Expedition 2022 to characterise biodiversity across the web of life. From a single shotgun assay per sample, this approach simultaneously characterised the sediment microbiome, which amplicon‐based surveys recover only through parallel, targeted assays, and extended detection to higher eukaryotes. Using high‐throughput sequencing, we generated 12.8 billion sequences, revealing taxa covering all domains of life. Although eukaryotic sequences represented only 0.7% of the taxonomically annotated dataset, we managed to identify 679 eukaryotic families. Prokaryotic diversity was high, as expected in a basin‐scale sampling coupled with high sequencing depth, with groups covering a wide functional array. Community structure analyses revealed depth‐driven stratification of open‐ocean benthic microbial communities and latitudinal structuring of coastal benthic eukaryotes. Overall, this dataset provides an empirical reliability–coverage trade‐off with direct consequences for the design of eDNA monitoring programmes targeting conservation‐priority taxa, and clear priorities for taxa specific reference‐database expansion.

Hydrological Regime Shifts Reshape Assembly Dynamics of Multi‐Trophic Microbial Communities in Pumping Station Forebays - Weiwei Song; Xiaofu Wei (Environmental Microbiology, 2026)
Multi‐trophic microbial community assembly and interactions in the forebays of pumping stations have remained poorly understood. In this study, 16S and 18S rRNA sequencing was carried out to reveal the diversity, network structure, assembly processes and environmental drivers of multi‐trophic microbial communities across normal and wet seasons in the pumping stations of the Qinhuai River Basin. The results showed that microbial diversity and community composition differed significantly between the two hydrological periods across all four trophic groups. Co‐occurrence network analysis indicated that the wet season network displayed greater complexity, connectivity and stability compared with the normal season network. Community assembly analyses revealed that dispersal limitation dominated in both seasons, whereas the relative contribution of homogeneous selection increased substantially during the wet season. Moreover, trophic transfer efficiencies were significantly correlated with β‐nearest taxon index (βNTI) values, suggesting an association between cross‐trophic interactions and assembly processes. Environmental analyses further showed that eukaryotic communities were jointly regulated by temperature ( T ), nitrogen nutrients and pH, whereas bacterial communities were mainly driven by T . These findings strengthen the understanding of how hydrological fluctuations regulate multi‐trophic microbial communities through the combined effects of environmental filtering and trophic interaction restructuring in pumping station ecosystems.

Spatiotemporal Forecasting of Mediterranean Blue Mussel Biofouling Settlement to Inform Aquaculture Management - Emrah Hancer; Romain Chaput; Ivy Liu; Bing Xue; Ross Vennell; Mengjie Zhang (New Zealand Journal of Marine and Freshwater Research, 2026)
Mediterranean blue mussel ( Mytilus galloprovincialis ) settlement significantly influences aquaculture productivity and biofouling management in New Zealand's coastal waters due to its rapid colonization of farming infrastructure and its competitive interactions with cultivated species. In this study, we develop a regression‐based forecasting framework to predict monthly Mediterranean blue mussel spat settlement using temperature‐driven temporal features. Key environmental predictors include mean air temperature and sea surface temperature (SST), along with their lagged and rolling derivatives, which capture both seasonal patterns and short‐term thermal dynamics. To account for spatial variability, geographically proximate monitoring sites are grouped into 11 representative clusters using a spatial clustering algorithm. Forecasting is performed with the XGBoost regression model, which is well suited to nonlinear ecological processes and feature interactions. Model performance is evaluated using a Leave‐One‐Group‐Out (LOGO) cross‐validation strategy to assess generalization to previously unseen locations. The results demonstrate strong predictive skill in multiple regions and highlight the potential of this approach to support proactive aquaculture management and mitigate settlement‐driven biofouling impacts.

Fish Futures in the Aftermath of the Invasion of Aotearoa New Zealand by the Freshwater Gold Clam ( Corbicula fluminea ) - Calum MacNeil (New Zealand Journal of Marine and Freshwater Research, 2026)
In 2023, the gold / Asian clam ( Corbicula fluminea ) was first recorded in Aotearoa New Zealand (Aotearoa‐NZ). This non‐native species (NNS) could impact Aotearoa‐NZ freshwater ecosystems more than any previous invader. It could alter food webs, physical habitats and water clarity, disrupt nutrient cycling and restructure plankton / macroinvertebrate / fish assemblages. I have reviewed clam impacts on trophic ecology, water chemistry and fish habitat from international studies, focusing on native and non‐native fish species also present in Aotearoa‐NZ and on ecological analogues. I identified fish that could be negatively affected and those which could benefit. Small benthic ‘riffle‐run specialists’ could be vulnerable to some extent, facing both habitat modification and competition for shared food resources. Fish frequenting backwaters or slower‐flowing reaches could be even more vulnerable, as clam densities are often highest here. Native galaxiids, already threatened by habitat fragmentation/degradation, may be at further risk from additional pressures of a clam invasion. Among introduced fish, salmonids may lose spawning habitats, whereas generalist ‘pests’ such as catfish and koi may benefit from clam‐derived food resources. C. fluminea may represent a significant new stressor for Aotearoa‐NZ freshwater ecosystems. The hyptheses generated in this article are important to help anticipate species‐specific responses, which will be essential for strategies to protect native fish.

Aquatic Mushrooms: Unraveling the Ecology, Evolution, and Biotechnology of Freshwater and Marine Macrofungi - Samantha C. Karunarathna; Saowaluck Tibpromma; Wenhua Lu; Hansika Perera; Baggya Sharmali Karunarathna; Dong‐qing Dai; Garumuni Dilrukshi Nadeeshani Menike; Kalani Kanchana Hapuarachchi (New Zealand Journal of Marine and Freshwater Research, 2026)
Terrestrial mushrooms dominate mycology; their aquatic relatives are a fascinating and ecologically significant group. Psathyrella aquatica , the sole single‐gilled genus with underwater‐reported fruiting bodies, and marine‐dwelling genera such as Nia and Halocyphina illustrate how Basidiomycota radiated to aquatic environments. These freshwater, marine, and brackish aquatic fungi are principal nutrient cyclers, wood decayers, and symbionts of aquatic habitats, but their biology and ecology are poorly known. Herein, our current knowledge of their diversity, evolutionary adaptations such as floatation spores, halotolerant enzymes, and hydrophobic fruiting bodies, and their potential biotechnological applications is reviewed. Marine mushrooms are a source of bioactive compounds with reported antimicrobial and anti‐inflammatory activities, and their enzymatic profiles, adapted to saline or submerged conditions, suggest potential for bioremediation applications. With global warming, there is a need to research aquatic mushrooms not just to preserve biodiversity but also to tap their potential for green technology. This review synthesizes current knowledge on targeted research and conservation efforts for aquatic mushrooms. This information is essential for both understanding global biodiversity and advancing biotechnological innovations.

Literature Review of Catchment Models in Aotearoa New Zealand for Ecological and Social Climate Change Effects - Margaret Armstrong; Deniz Özkundakci (New Zealand Journal of Marine and Freshwater Research, 2026)
Shifting climatic averages and extremes are affecting both environmental and anthropogenic communities. This is a growing concern, especially for social–ecological systems (SES) such as lakes and their catchments, which integrate ecological and societal subsystems. Models are frequently used for research and management of these SESs, although these tools may not be capable of simulating processes from both subsystems. We conducted a literature review to assess the ability of ten catchment models commonly applied in Aotearoa New Zealand to simulate broad climate change effects. Assessment criteria represented the ecological system (hydrology, sediment transport, contaminants) and social system (economics, cultural values) of lake catchments. All of the reviewed catchment models demonstrated capacity for simulating one or more ecological criteria, while only three addressed the economics criteria within the social system. Based on these findings, we discuss model trade‐offs and highlight options for more holistically incorporating the social system into models of SESs. Advancing the development and applications of such models will provide a basis for more integrated and effective management in the years to come.

Greeffiella bellula n. sp. (Nematoda: Desmoscolecida): The First Desmoscolecid Nematode Species to Be Described From New Zealand - Daniel Leduc; Zeng Qi Zhao (New Zealand Journal of Marine and Freshwater Research, 2026)
The mostly marine nematode order Desmoscolecida is globally distributed with over 270 species known to date. Here, we describe Greeffiella bellula n. sp., the first desmoscolecid species to be described from New Zealand waters, from deep‐sea sediments. The new species is most similar to G. japonica , described from coastal sediments in the Sea of Japan, in having relatively few ( Greeffiella bellula n. sp. can be most easily differentiated from the latter by the different body shape and in having fewer pairs of subdorsal setae. A dichotomous key to the 15 valid species of the genus is presented. Results of SSU phylogenetic analyses based on 19 Desmoscolecidae sequences confirmed the genus assignment of the new species, but unlike previous analyses did not provide support for the monophyly of the subfamilies Desmoscolecinae and Tricominae, or of the closely related genus Desmoscolex .

Growth and Bromoform Content in At‐Sea Grown Asparagopsis armata Gametophytes: A Short Communication - Cecilia Biancacci; Joshua Fitzgerald; Paul M. South (New Zealand Journal of Marine and Freshwater Research, 2026)
Asparagopsis armata has international commercial relevance due to its high bromoform content, which can reduce the methane emissions from cattle when incorporated into their diet. However, few studies have reported on at‐sea cultivation techniques and their effect on bromoform content in A. armata. In this study, we assessed the effects of seeding density (150, 300 and 600 g WW m −1 ) on the specific growth rate (SGR) and bromoform content of A. armata in suspended culture on a marine farm. We also tested whether transport conditions affected bromoform content, comparing emersed and immersed A. armata biomass after 3.5 h. Seeding density had a strong effect on the SGR of A. armata with the lowest seeding density having significantly greater growth (1.5 to 5 times) than higher seeding densities. Transporting the A. armata biomass in seawater increased its bromoform content (by 73.6%) relative to the immersed material. These findings will inform efficient approaches to the sea‐based culture of A. armata .

A Niche for Nasty Nippers: Exploring Harvest Management for Control of Invasive Asian Paddle Crabs in Aotearoa New Zealand - Anjali Pande; Samik Datta; Yvonne Matthews; Paula Holland; Michael Beentjes; Matt Smith; Sean Handley; Graeme J. Inglis (New Zealand Journal of Marine and Freshwater Research, 2026)
The invasive Asian paddle crab Charybdis japonica continues to expand its range across northern Aotearoa New Zealand, raising ecological, social, and economic concerns. This study theoretically assesses whether harvest‐based management—potentially including commercial, recreational, or customary fisheries—could contribute to population suppression. Five key factors were examined: consumer demand, fisher willingness to supply, population abundance in Whangarei Harbour, comparison with the native Ovalipes catharus fishery, and legal constraints, making up a theoretical framework within which to assess the feasibility of harvest exploitation as a management tool. Consumer surveys revealed strong interest in purchasing invasive crab products, with respondents valuing both taste and the ecological benefits of control. Fisher surveys indicated moderate to strong willingness to harvest C. japonica , though uncertainty remains around saleability and regulatory permissions. However, a stratified trap survey in Whangarei Harbour found unexpectedly low catches of the crab, suggesting the current population there cannot sustain a fishery. Comparison with the declining O. catharus fishery highlights potential market space, but also underscores ecological risks. Legally, regional vs national pest designations under the Biosecurity Act, as well as fishery regulations, present significant barriers to the ability to enact harvest control. Overall, while market and fisher interest appear promising, biological and regulatory constraints currently limit the feasibility of a harvest‐control fishery for C. japonica . This study contributes to the ongoing discourse of methods available for invasive species management.

Impact of Elevated Suspended Sediment on the Physiology of the Temperate Sponge Suberites australiensis - Georgia R. Ryan; Lisa Woods; James J. Bell (New Zealand Journal of Marine and Freshwater Research, 2026)
Suspended sediment (SS) is a major stressor to coastal marine ecosystems worldwide, with SS loads expected to increase under future anthropogenic and climatic pressures. Sponges, as obligate filter feeders, are often assumed to be sensitive to elevated SS, yet responses vary widely among species, and little is known about physiological impacts of SS. Here, we examined the response of the abundant temperate sponge Suberites australiensis to prolonged pulses of suspended sediment, simulating conditions in Wellington Harbour, New Zealand, during rain and storm events. Sponges ( n = 42) were exposed to daily 7 h pulses (to mimic natural variation) of fine kaolin clay (25–35 μm) over 19 days at suspended sediment concentrations (SSC) of 120–150 mg l −1 , while controls received only filtered seawater. Physiological responses were assessed through changes in buoyant weight and respiration rates at four time points. No significant differences in respiration rates were detected between treatments and controls, and there was no visible tissue necrosis or morphological deterioration in any of the sponges. Treatment sponges exhibited a significant increase in buoyant weight relative to controls. These findings indicate that short periods of high level exposure to suspended sediment load have no physiological impact on S. australiensis and this species likely uses passive mechanisms to survive SS stress. This resilience may enable the persistence of S. australiensis in sediment‐impacted coastal environments; however, thresholds that may impact physiological performance remain unknown.

Site and Season Influence the Success of Seagrass Transplantation in Aotearoa New Zealand - Dan Crossett; Jessica Barr; Alba Cervantes‐Loreto; Irisa Hudson; Anna Berthelsen; Dana E. Clark (New Zealand Journal of Marine and Freshwater Research, 2026)
Seagrasses are important ecosystem engineers that create nursery habitat for fish, support high biodiversity, enhance water quality and store carbon. However, seagrasses are declining globally, including in many places in New Zealand. One approach to counter these losses is shoot‐based seagrass restoration, which involves transplanting adult seagrass plants together with their surrounding sediment and associated communities. We investigated the feasibility of shoot‐based restoration by transplanting 150 mm plugs of seagrass ( Zostera muelleri ) from donor seagrass meadows to nearby unvegetated soft sediment at two sites in Nelson Haven, New Zealand. Sites differed in donor meadow age (old vs. new) and environmental conditions. We also tested whether transplant season (winter vs. summer) influenced success. Transplant success was monitored over 2 years and determined by an increase in seagrass area, blade number, and blade length. Bayesian modelling showed that both site and season influenced success. The best‐fit model showed greater success when transplants from the ‘older’ donor meadow, which had higher seagrass cover, lower mud content and shorter tidal exposure, performed better than those from the ‘newer’ meadow. Model predictions also indicated greater success in winter than in summer. Empirical observations supported these patterns; for example, we observed 30% survival of transplants at the older site after winter transplantation, whereas zero transplants survived after summer transplantation or at the ‘newer’ meadow. There were no obvious detrimental effects of seagrass removal from donor meadows, and this study shows that transplanting Z. muelleri with an intact sediment community can be an effective restoration method in intertidal habitats, though success is highly context dependent. This study gives practical insights to guide future seagrass‐restoration efforts.

Effects of Climate Change on Aquaculture and Fisheries: Current and Future Impacts, Mitigation and Adaptation - Natalí J. Delorme; Craig Stevens; Bradley Skelton; Jessica A. Ericson (New Zealand Journal of Marine and Freshwater Research, 2026)

Changes in the Diet of Antarctic Shags ( Leucocarbo bransfieldensis ) Among Breeding Colonies and Over Time at Danco Coast, Antarctic Peninsula - Marianela Beltran (New Zealand Journal of Marine and Freshwater Research, 2026)
Coastal waters along the Danco Coast, western Antarctic Peninsula, form a highly productive ecosystem that supports a high abundance of top predators. However, this region is experiencing accelerated environmental change, leading to significant changes in prey availability and food‐web structure. In this context, predator diets provide valuable indicators of ecosystem status. The diet composition of Antarctic shags ( Leucocarbo bransfieldensis ) during the 2018 chick‐rearing period at three breeding colonies was investigated through pellet analysis ( N = 91). Antarctic shags primarily consumed demersal–pelagic prey. Dominant prey species were Antarctic black rockcod ( Notothenia coriiceps ) and Dusky notothen ( Trematomus newnesi ), with colony‐specific variation. No significant changes were detected between chick‐rearing stages; however, a gradual decline in the number and mass of the N. coriiceps , and an increased contribution of smaller prey species, such as T. newnesi and H. antarcticus, was detected as the chicks approached fledging. The results are compared with previously published dietary data from the same area and discussed in relation to potential long‐term variability in prey availability and implications for ecosystem monitoring.

Mapping Functional Indicators for Evaluating Mangrove Rehabilitation Effectiveness: A Systematic Literature Review - Rihul Janna; Fredinan Yulianda; Fery Kurniawan (New Zealand Journal of Marine and Freshwater Research, 2026)
Mangrove rehabilitation is increasingly implemented to restore degraded coastal ecosystems, yet most evaluations remain dominated by structural indicators such as canopy cover or seedling survival. This study conducts a systematic literature review under the PRISMA 2020 protocol to identify and classify functional indicators used in mangrove rehabilitation assessments. From 55 Scopus‐indexed publications, 17 articles met the inclusion criteria, yielding 82 functional indicators. These indicators were grouped into 12 categories, with carbon emerging as the most dominant, particularly carbon sequestration and soil organic carbon. In contrast, other functional dimensions such as trophic interactions, microbial processes, and socio‐cultural services remain underexplored. This imbalance indicates that current monitoring approaches still emphasise structural and conceptual aspects rather than functional recovery. The study highlights the need to integrate functional indicators into rehabilitation monitoring to comprehensively capture ecosystem processes, resilience, and socioeconomic benefits. The findings provide a scientific basis for developing holistic evaluation approaches and guiding sustainable mangrove management, while also offering comparative insights relevant to the Southern Hemisphere context, where mangroves play critical ecological roles.

Stable Isotope Analysis of New Zealand Fur Seal Vibrissae Shows Deceased Juveniles Were Weaned Early - Diana Galbraith; B. Louise Chilvers (New Zealand Journal of Marine and Freshwater Research, 2026)
The New Zealand fur seal/kekeno ( Arctocephalus forsteri , NZFS) is a marine predator native to Aotearoa/New Zealand. Little is known about its fine‐scale dispersal around New Zealand in the nonbreeding season. As an alternative to external marking or electronic tracking, stable isotope analysis was trialed to determine the origin of stranded (deceased) NZFS young‐of‐the‐year (YOY). Vibrissae were collected opportunistically from YOY at nonbreeding sites on the east and west coasts of Northland and Hawkes Bay, New Zealand. Vibrissa growth rates and estimated vibrissa lengths at birth were calculated using samples from pups at established breeding colonies and stranded YOY. The δ 13 C and δ 15 N values at breeding colonies and in YOY were not sufficiently isotopically distinct to determine the colony of origin. Isotopic niche widths were greater for YOY than for pups from the same breeding season. For YOY, isotopic niche widths were greater after weaning than preweaning, implying weaned NZFSs foraged more diversely than their mothers. Based on the assumed median pupping date, the estimated maximum age at weaning for stranded YOY was 223–247 days, which is considerably less than previously published weaning data for NZFSs. Early weaning may contribute to increased juvenile mortality.

Optimizing Stocking Density Under Semi‐Movable Paddlewheel Aeration to Improve Water Quality, Growth Performance and Production of Nile Tilapia Reared in Concrete Ponds - Mohamed N. El‐Rewiny; Attia A. Abou Zaid; Mohamed M. Abdel‐Rahim; Ashraf I. G. Elhetawy; Mohamed A. Bauomi; Wasseem Emam; Radi A. Mohamed (New Zealand Journal of Marine and Freshwater Research, 2026)
This study evaluated the effects of increasing stocking density under a fixed aeration capacity on water quality, growth performance, and economic efficiency of Nile tilapia ( Oreochromis niloticus ) cultured in concrete ponds equipped with a semi‐movable paddlewheel aeration configuration. Three stocking densities (80, 120, and 160 fish m −3 ) were tested over a 90‐day production cycle using a completely randomized design with triplicate ponds per treatment (each 99 m 3 ). The aerators were operated continuously (1.5 hp, 24 h day −1 ), and aeration power was kept constant across treatments. Water quality showed a clear density‐dependent deterioration: dissolved oxygen (DO) decreased from 5.0 ± 0.17 mg L −1 at 80 fish m −3 to 3.3 ± 0.17 mg L −1 at 160 fish m −3 ( p −1 to 0.056 ± 0.01 mg L −1 . In line with this, the growth performance decreased as density increased: the final body weight decreased from 304.3 ± 0.882 g to 272.7 ± 5.903 g, and the feed conversion ratio increased to 1.68. Survival rate showed a moderate decline to 93.2%. Whereas the highest density had the highest total biomass (3,969 kg) and gross revenue (US$8,972), the intermediate density (120 fish m −3 ) had the most balanced result between growth performance, survival, and profitability (benefit‐cost ratio = 1.49). The highest stocking density was associated with lower DO, increased nitrogen loading, and reduced size uniformity, suggesting that production efficiency was mainly constrained by oxygen availability and overall biomass loading rather than by acute ammonia toxicity. These results imply that, when the aeration capacity in concrete pond systems is held constant, moderate stocking density can be best suited to a trade‐off between biological performance and economic payoff and can be useful in the context of intensive Nile Tilapia production in situations with limited aeration capacity.

Historical Records of Tumours in New Zealand Marine Fishes - John Brian Jones (New Zealand Journal of Marine and Freshwater Research, 2026)
Tumours were first described in New Zealand marine fishes in 1982 but those early records have been difficult to access and subsequently few tumours have been collected and little has been published. This review updates records of identified tumours from teleosts in the New Zealand marine environment and may encourage more work to identify background tumours in a rapidly changing and increasingly polluted marine environment.

Swimming Under the Radar: Trout‐Free Kōaro Populations in Aotearoa Lakes and Tarns Are Rare, Understudied, and Disappearing - Lauren G. Hitt; Simon D. Stewart; Nixie C. Boddy; Angus R. McIntosh (New Zealand Journal of Marine and Freshwater Research, 2026)
Over the last 150 years, most large, easily accessible lakes and tarns in Aotearoa (New Zealand) have experienced trout introductions or incursions, leaving few salmonid‐free reference lakes. Using database information and field surveys, we characterized lake, pond/tarn, and wetland systems found throughout Aotearoa that support populations of kōaro ( Galaxias brevipinnis ) known or putatively believed to be trout‐free. These systems require more research because our existing knowledge is outdated, patchy, and largely unacknowledged, while their kōaro populations may be increasingly vulnerable. Although persisting trout‐free kōaro populations tend to be found in small, isolated, and difficult to access lakes, at least 10% and potentially up to 22% of known trout‐free kōaro populations may have already been lost in the last 20 years. The causes of these losses are varied and highlight the sensitivity of the remaining populations, which are likely genetically isolated and evolutionarily significant. Historic and modern threats to these remaining kōaro populations include incursions of introduced fishes and worsening climate impacts. Lakes supporting isolated kōaro populations hold substantial conservation value, require more consistent monitoring to prevent additional losses of irreplaceable populations, and need targeted conservation of this important taonga (treasured species) consistent with the diversity they contribute to Aotearoa's broader freshwater biodiversity.

Identifying Timing, Cues, Site Characteristics and Threats to Shortjaw kōkopu Spawning in Two Northland Streams - F. M. A. Donovan; T. D. Donovan; K. H. Donovan (New Zealand Journal of Marine and Freshwater Research, 2026)
The shortjaw kōkopu ( Galaxias postvectis ) is the most threatened of New Zealand's diadromous galaxiids. Cryptic, nocturnal behaviours and their rarity mean ecological knowledge remains limited. Two sites in Northland (Waiotemarama Stream and Okawawa Stream) were monitored from March–July for 3 years to gather population data and information on spawning cues, timing, spawning site habitat and threats to spawning success. Fifteen shortjaw kōkopu spawning sites were identified throughout the study period above the wetted stream margins following spate flows in May–June. It is hypothesised that altered flow regimes, as a result of climate change, may impact spawning success through effects on spawning habitat, resource availability and the premature inundation of eggs. During monitoring, we identified the predation of eggs at multiple spawning sites by rats ( Rattus norvegicus , Rattus rattus ). A rodent control operation was established at two sites in an attempt to limit egg predation and increase the number of eggs reaching full development. Predator control results were variable, and a clear relationship between rat predation, rat control and spawning site outcomes was not identified. However, this study suggests the need for the consideration of pest management in the conservation of native freshwater fish in New Zealand.

Two Germans, a Swede, and a Giant kōkopu: The Background to the Earliest Documented Description of a New Zealand Freshwater Fish - James Braund (New Zealand Journal of Marine and Freshwater Research, 2026)
Galaxiids are a family of scaleless and mostly small freshwater fish which are distributed across the temperate latitudes of the southern hemisphere. The largest member of this family is the giant kōkopu ( Galaxias argenteus ), which has the added distinction of being the first New Zealand freshwater fish of any kind to be scientifically described. This description was produced by naturalists on board James Cook's HMS Resolution when they visited Dusky Sound in the far south of New Zealand in the autumn of 1773, and it represents, among other things, a fascinating intersection of history and science. This article, which is primarily historical in its approach, revisits the original documentary records describing the giant kōkopu that were left by Cook's naturalists, and argues that the descriptive process involving this fish was much more of a team effort than has previously been assumed.

Long Term Remediation of a Chemical Barrier to Fish Migration Restores Natural Demographics of Headwater Galaxias brevipinnis Population - O. R. Hore; D. P. Gray; P. Lindsay (New Zealand Journal of Marine and Freshwater Research, 2026)
Acid and metalliferous drainage (AMD) reduces fish diversity with effects extending downstream. Discharges may also create chemical barriers for migratory species into otherwise unimpacted headwaters. We investigated kōaro ( Galaxias brevipinnis ) response to remediation of an AMD‐impacted tributary in a 5 th ‐order West Coast, New Zealand river. Kōaro communities were surveyed once pre‐remediation and on seven subsequent occasions between 2005 and 2024, at six sites within the Ngākawau catchment and two reference streams, using backpack electric‐fishing. Aluminium, pH and turbidity measurements were analysed for temporal patterns and exceedances of threshold values of fish sensitivity, derived for naturally acidic West Coast streams. Significant differences in kōaro demographics were observed between pre‐ and post‐remediation surveys. 2 years post‐remediation, kōaro abundance had increased, dominated by juveniles 100 mm. Current abundance and size distribution, plus interannual demographic constancy, suggest the population is stable and not recruitment limited.

Issue Information (New Zealand Journal of Marine and Freshwater Research, 2026)

How Speculation Became Accepted Truth: Evidence that Aotearoa New Zealand Freshwater Eels Do Not Seem to Spawn “Near Tonga” or “East of Samoa” - Amandine J. M. Sabadel; Michael J. Miller (New Zealand Journal of Marine and Freshwater Research, 2026)
For several decades, the assumption that Aotearoa New Zealand freshwater eels spawn near Tonga (for longfin, Anguilla dieffenbachii ) or east of Samoa (for shortfin, A. australis ) has been widely repeated across scientific literature, governmental reports, public resources and community narratives, despite limited direct evidence. These claims originated from early scientific speculation and were not updated as new evidence emerged. This illustrates how preliminary ideas can become entrenched as accepted truth through repetition and raises a broader question: how can new scientific findings be communicated effectively when they challenge long‐standing narratives?.

Issue Information (Reviews in Aquaculture, 2026)

Into the Wild: Farm‐Derived Energy and Nutrients Enter Marine Food Webs With Carrying Capacity Implications for Aquaculture Management - Myriam D. Callier; Ramon Filgueira; Carrie J. Byron; Daniele Brigolin; Dror L. Angel; Sophie J. I. Koch; Bobbi Hudson; Frank Kane; Heather Moore; Antonio Agüera; Lotta C. Kluger; Christopher W. McKindsey (Reviews in Aquaculture, 2026)
Marine aquaculture is expanding globally, yet its interactions with surrounding ecosystems remain complex and insufficiently understood. This study reviews the fluxes of energy and nutrients from three major aquaculture systems: finfish cages, suspended bivalves, and seaweed farms and considers their implications for ecosystem functioning and management under the ecosystem approach to aquaculture (EAA). Using a focused literature review and expert input from International Council for the Exploration of the Sea (ICES), Working Group on Ecological Carrying Capacity of Aquaculture (ICES WGECCA), we synthesized data on farm‐derived fluxes, trophic transfers, and ecological consequences. From this synthesis, we developed three conceptual models illustrating direct and indirect pathways of energy and nutrient exchange between farms and marine food webs. Seven case studies from temperate and subtropical systems were analyzed to exemplify site‐specific effects, including organic enrichment, altered benthic‐pelagic coupling, and changes in wild species assemblages. Key findings highlight that fed aquaculture (finfish) releases substantial particulate and dissolved waste, influencing benthic geochemistry, while extractive systems (bivalves, seaweeds) modulate nutrient cycling. Integrated multi‐trophic aquaculture (IMTA) offers the potential for synergistic flux recycling within the farm system. Wild mobile fauna attracted to farm systems shelter and feed directly on the farmed product, fouling, or particulate wastes and dislodgements from the farm, thereby strengthening farm‐environment coupling. These insights underscore the need for adaptive management and carrying capacity (CC) assessments that account for energy‐nutrient fluxes to ensure sustainable aquaculture development aligned with EAA principles.

The Application of Herbal Medicines for Parasites Control in Aquaculture: A Review - Xiaoping Tan; Chengzhong Yang; Qianwen Zhou; Shenye Qu; Tianqiang Liu; Fei Ling; Gaoxue Wang (Reviews in Aquaculture, 2026)
With the ongoing expansion of intensive aquaculture, the emergence of parasite drug resistance and the increasing frequency of disease outbreaks have become significant challenges. Conventional antiparasitic agents are increasingly restricted due to burgeoning resistance, environmental persistence, and safety concerns. Consequently, the development of eco‐friendly and sustainable therapeutic alternatives has emerged as a primary research priority. Herbal medicines (HMs), characterized by a vast reservoir of structurally diverse and bioactive compounds, serve as ideal candidates for drug discovery in aquaculture. In recent years, substantial research effort has been directed toward identifying commercially viable HM‐derived agents for the fish farming industry. Advancements in isolation and purification technologies have facilitated the extraction of numerous insecticidal small molecules, while further studies have elucidated their underlying antiparasitic mechanisms. This review provides a comprehensive analysis of the role of HMs in preventing and treating aquatic parasitic infections, encompassing the isolation of active constituents, evaluation of efficacy, modes of action, and optimization of application strategies. Furthermore, we address the inherent challenges and future trajectories of utilizing HMs in aquaculture. By synthesizing current knowledge on these bioactive compounds, this review aims to facilitate the development of safe, highly bioavailable, and environmentally sustainable antiparasitic agents.

Plant‐Derived Treatments for Monogenean Parasites in Farmed Fish: A Systematic Review and Meta‐Analysis - Francisco Neptalí Morales‐Serna (Reviews in Aquaculture, 2026)
Monogeneans are among the most problematic ectoparasites in finfish aquaculture. Plant‐derived compounds have been widely explored as therapeutic agents, yet their efficacy and safety have not been quantitatively synthesized across studies. This study provides a meta‐analysis of plant‐based treatments against monogeneans, integrating 453 in vitro and 262 in vivo treatment comparisons from 50 publications. Random‐effects and multilevel models were used to estimate pooled efficacy, assess heterogeneity, and evaluate patterns across compound types, concentration categories, and exposure durations. Safety was assessed using therapeutic indices or margins of safety derived from acute‐toxicity endpoints. Most studies focused on dactylogyrids and gyrodactylids infecting two freshwater fish species. Plant‐derived treatments produced consistently strong antiparasitic activity in vitro and in vivo (overall parasite‐load reduction ~75%–80%), although with substantial methodological heterogeneity. Isolated compounds were the only group achieving high mortality at low concentrations and short exposures, whereas crude extracts and essential oils generally required higher concentrations or longer treatments. Safety outcomes showed no consistent relationship with concentration, and only 18% of treatments achieved complete parasite elimination while remaining safe for fish. Notably, some studies recommended treatment regimens even when their results did not clearly support strong therapeutic performance, highlighting the need for more explicit standards for defining effective and safe therapies. Overall, plant‐derived compounds show promise for managing monogenean infections, but strong efficacy does not guarantee practical or safe application. Integrating in silico approaches, combining ligand‐based screening with parasite‐specific molecular targets, offers a promising route to prioritize candidates with genuine therapeutic potential in aquaculture.

Herbal Medicines and Probiotics: Synergistic Applications for Sustainable Aquaculture and Future Optimization - Xiao Yan; Jiali Mi; Chaobin Qin; Guoxing Nie (Reviews in Aquaculture, 2026)
With the transformation of aquaculture toward green and sustainable development, the research and application of natural feed additives have become a research focus in the field. As two types of green additives with high efficiency and low residue, herbal medicines and probiotics show significant potential in improving the health of fish and enhancing aquaculture benefits. This paper systematically reviews the research progress of their applications in aquaculture, summarizing the core active components of herbal medicines as well as their mainstream isolation and purification techniques. It further analyzes the high functional consistency between the two in promoting growth performance, regulating gut microecological balance, enhancing immune function, optimizing nutritional metabolism, and improving muscle nutritional composition and quality. Moreover, this paper illustrates the synergistic interaction modes of herbal medicines and probiotics. Their combined application produces functional superposition and mutual complementation, which jointly enhance physiological regulation. More importantly, the interaction between herbal medicines and probiotics during the production of fermented herbal medicines is more pronounced. It can generate new active substances, increase the concentration of effective components, and promote digestion and absorption, thus greatly enhancing the overall physiological regulatory effect. Finally, the paper identifies current research limitations and prospects future directions, highlighting that artificial intelligence can help achieve full‐cycle intelligent control and precise application of herbal medicines and probiotics in aquaculture. This review will provide new insights to address practical industrial challenges, thereby providing a comprehensive reference for the theoretical research and practical application of green feed additives in aquaculture.

Infectious Diseases Management in Small‐Scale Freshwater Aquaculture in West Africa: Lessons for Low‐ and Middle‐Income Countries - Mame Boucar Diouf; Robane Faye; Ahou Rachel Koumi; Nounagnon Darius Tossavi; Enoutchy Fabrice Bouah; Ephigénie Ndew Dione; El Hadji Malick Sy Camara; Kadjo Henri Joel Niamien; Ué Clavier Zéa Bi; Atto Delphin Kouadio; El Hadji Papa Abdourahim Sy; Thérèse Adeline Fatou Gomis; et al. (Reviews in Aquaculture, 2026)
Infectious diseases are an increasing threat to food security, small‐scale livelihoods and the sustainability of aquaculture in low‐ and middle‐income countries (LMICs). In sub‐Saharan Africa, aquaculture is expanding rapidly but production systems often remain fragile. In West Africa, particularly in Benin, Côte d'Ivoire and Senegal, production remains modest despite rising demand. Interactions between farming practices, environmental exposures (e.g., contaminants and agricultural effluents) and pathogen emergence are poorly documented. Here we review evidence on production systems, reported pathogens, diagnostic and surveillance capacity in these three countries. We find that (i) production relies mainly on small‐scale ponds, cages often within integrated agro‐aquaculture systems with recurring constraints in biosecurity, water management and governance; (ii) available evidence is fragmented and uneven across pathogen groups, with most reports focusing on bacterial and parasitic conditions and major gaps for viruses, fungi, co‐infections, antimicrobial resistance and combined environmental pressures; and (iii) health management and laboratory capacities remain constrained, but existing networks and experience from terrestrial animal health provide entry points for integrated and participatory surveillance. We discuss these patterns through an exposome‐informed One Health lens, highlighting how multiple exposure pathways link farms, watersheds and nearby communities. Based on this synthesis, we outline research and policy priorities to strengthen health resilience and to support more sustainable small‐scale freshwater aquaculture in West Africa and, with relevance to other tropical LMIC settings.

Research in Fish Polyculture Worldwide: Global Patterns, Trends, Knowledge Gaps, and Future Directions - M.‐L. Tchiedjo; M. Thomas; F. Pétronin; P. Kestemont; T. Lecocq (Reviews in Aquaculture, 2026)
Fish polyculture is the concurrent rearing of multiple fish species within the same aquaculture system. It represents one of the oldest and most adaptable strategies for enhancing aquatic food production. While its ecological and economic potential is widely acknowledged, a comprehensive understanding of global patterns of research on fish polyculture remains lacking. This study provides a systematic synthesis of scientific literature over 55 years (i.e., published between 1968 and 2023), following the PSALSAR methodology. Using the Web of Science database, 889 peer‐reviewed articles were screened, of which 220 met inclusion criteria. Each study was analyzed for species composition, production systems, research objectives, and management strategies. Results show a strong geographic bias, with research predominantly originating from Asia, while Africa, Europe, and the Americas remain underrepresented. Freshwater pond systems dominated the research landscape, and most studies focused on growth performance and yield optimization rather than ecological or socioeconomic outcomes. However, recent publications indicate a shift toward sustainability‐oriented approaches, including integrated multi‐trophic aquaculture, biofloc systems, and rice–fish ecosystems. Analyses revealed emerging research themes linking species diversity, nutrient recycling, and ecological efficiency. This review provides the first global overview of fish polyculture research, highlighting major trends as well as global and regional gaps. Future work should emphasize ecosystem function, animal welfare, and the integration of circular economy principles to enhance the contribution of fish polyculture to sustainable aquaculture development.

The Narrow‐Clawed Crayfish Pontastacus leptodactylus : Biology, Culture Development, and Prospects for Sustainable Aquaculture - Ardavan Farhadi; Muzaffer Mustafa Harlıoğlu; Erchao Li (Reviews in Aquaculture, 2026)
Pontastacus leptodactylus is a freshwater crayfish native to the Ponto‐Caspian region, with a distribution across Eastern Europe and Western Asia. This review synthesizes current knowledge on the biology, culture development, and prospects for sustainable aquaculture of P. leptodactylus . Commercial exploitation of P. leptodactylus has a long history in Western Europe and the Ponto‐Caspian region and has relied primarily on capture fisheries. Türkiye served as the principal exporter to international markets until the 1985 outbreak of crayfish plague ( Aphanomyces astaci ), which precipitated widespread stock collapses. In contrast, aquaculture development remained limited for decades and has only recently gained momentum, particularly, in China. Following the first identification of P. leptodactylus in China in 2021, interest in its culture has increased, with pilot‐scale farming trials and localized hatchery activities reported across several provinces. However, production remains limited in scale, and these developments are best regarded as early‐stage or proof‐of‐concept initiatives rather than established commercial aquaculture. Accordingly, this review provides an integrated appraisal of culture practices, including broodstock management, artificial incubation, juvenile feeding, stocking strategies, grow‐out systems, and health and biosecurity protocols. It further synthesizes market dynamics, value‐chain development, and welfare considerations alongside performance benchmarks. Key constraints such as the lack of species‐specific feeds, limited tools for cannibalism mitigation, and the absence of selective breeding programs are identified as major barriers to sustainable scale‐up. This review offers a framework to guide future research, management decisions, and aquaculture development for the sustainable utilization of P. leptodactylus .

The Invisible Farm: Rethinking What Intensive Aquaculture Does to Fish - Giovanni M. Turchini (Reviews in Aquaculture, 2026)

Antifouling in Marine Aquaculture: Mechanisms, Strategies, and Sustainable Design Guidelines - Channa Hamadullah; Pan Cao; Xiaodan Liu; Shuyan Miao (Reviews in Aquaculture, 2026)
Antifouling remains a critical constraint on the expansion of marine aquaculture, yet existing knowledge is fragmented across materials science, hydrodynamics, ecology, and farm economics. This review synthesizes mechanistic understanding of marine biofouling and corrosion on aquaculture infrastructure through a structured literature review of more than 200 primary studies and reviews spanning materials science, hydrodynamics, ecology, environmental assessment, operational management, and system‐level antifouling design. Major strategy classes, including biocidal self‐polishing coatings, copper‐alloy meshes, foul‐release silicones, hydrophilic, zwitterionic, amphiphilic, photocatalytic, nanocomposite, and biomimetic systems, are evaluated alongside non‐coating operational measures such as robotic cleaning and hyperspectral monitoring. By comparing their performance, environmental profiles, and implementation constraints, the review translates current evidence into system‐level design guidance for marine aquaculture. Findings highlight the multiscale nature of biofouling impacts on drag, dissolved oxygen, structural integrity, and ecosystem responses, and show that no single technology dominates across performance, environmental risk, and cost. The review provides integrated design and reporting checklists, a multi‐criteria decision workflow for selecting coatings and structures, and an environmental risk matrix for major strategy types. A forward‐looking roadmap outlines priorities for adaptive multifunctional materials, farm‐scale modeling, and coordinated governance, providing a mechanism‐informed, system‐level foundation for antifouling in marine aquaculture.

Emerging Applications of Additive Manufacturing in Aquaculture Systems: A Comprehensive Review - Subha M. Roy; Hyunsoo Choi; Taeho Kim (Reviews in Aquaculture, 2026)
This review provides a comprehensive analysis of the existing literature on additive manufacturing, commonly known as three‐dimensional (3D) printing, in aquaculture systems. Among emerging technological innovations, 3D printing has gained increasing prominence in aquaculture operations due to its capacity to enable customized design, facilitate rapid prototyping, and improve operational efficiency. The integration of 3D printing into aquaculture offers advanced and innovative solutions and represents a promising pathway toward the development of smart aquaculture systems. This review critically evaluates various additive manufacturing technologies, their applications within the aquaculture sector, and relevant case studies. Publication trends, citation patterns, and patent activity from 2010 to 2025 are also analyzed. Furthermore, the review categorizes and assesses the benefits, challenges, and limitations associated with the adoption of 3D printing in aquaculture. Future research priorities are identified, with particular emphasis on sustainable materials, durability testing under aquaculture conditions, cost‐feasibility frameworks, and closed‐loop digital design–manufacturing workflows. By highlighting the role of 3D printing in aquaculture, this review addresses an emerging area of research and fills an important gap in the literature. The presented insights aim to guide researchers, industry stakeholders, and policymakers in advancing the integration of 3D printing technologies within the aquaculture sector.

Cover Image - Yinnan Mu; Weini Zhang; Pan Qin; Wenxing Li; Zhengwei Cui; Yang Ding; Jingqun Ao; Jiangtao Gao; Xinhua Chen (Reviews in Aquaculture, 2026)
The cover image is based on the article Elucidating the Immunological Basis of Large Yellow Croaker Larimichthys crocea Offers New Strategies for Its Disease Management by Yinnan Mu et al., https://doi.org/10.1111/raq.70164 . image

Risk Is Not Equal to Impact: The Challenges of Developing a Traffic Light System to Regulate Farmed Salmon Production on an Ecosystem Scale - Doris Soto; Rodrigo M. Montes; Renato A. Quiñones; Jorge León‐Muñoz; Marcelo E. Fuentes; Ruben Avendaño‐Herrera; Elias Pinilla; Jessica Fuentes; Carlos Chávez (Reviews in Aquaculture, 2026)
We review information on salmon farming production, environmental and climatic variables covering all salmon farming areas in the Patagonia marine ecosystems over a 10‐year period in Chile. With this information, we develop a semi‐quantitative Environmental and Productive Risk Assessment (RA) model as a guide for the design of a Traffic Light System (TLS) for salmon farming in Chile that ensures the minimizing impacts to ecosystems and to farmed salmon themselves. This interdisciplinary study is based on the compilation and integration of historical databases from multiple public and private institutions. These databases contain information on production, fish health, oceanographic and climatic information from 79 Salmon Farming Concessions Groupings (ACS) from 2012 to 2022. The model reveals that the highest Environmental and Productive Risks occur where high cumulative production pressure (Hazard) coincides with high Environmental Sensitivity, primarily in the fjords of the Los Lagos and Aysén regions. The study provides a risk‐based approach to prioritize monitoring and promote precautionary management in high‐risk areas while there is not enough information on ecosystem‐level tipping point indicators. Further development of a robust TLS requires the collaborative validation of ecosystem‐scale data and involving all relevant stakeholders in a participatory process to establish agreed‐upon risk thresholds and governance mechanisms for its implementation.

Cover Image - Subha M. Roy; Hyunsoo Choi; Taeho Kim (Reviews in Aquaculture, 2026)
The cover image is based on the article Emerging Applications of Additive Manufacturing in Aquaculture Systems: A Comprehensive Review by Subha M. Roy et al., https://doi.org/10.1111/raq.70154 . image

Biocontrol for Shrimp Disease: Comprehensive Review and a Bacterial Disease Biocontrol Practice - Xinyi He; Jian He; Minghong Liu; Menghuang Xu; Jianjun Jiang; Minze Liao; Chengcheng Wu; Peiyun Han; Long Zhang; Shaoping Weng; Zhixun Guo; Jianguo He (Reviews in Aquaculture, 2026)
Biocontrol is a key strategy for disease control, as it is environmentally friendly and widely applicable. This review elaborates on biocontrol in aquaculture, particularly in shrimp culture. Biocontrol in shrimp culture mainly relies on four strategies: (i) direct kill pathogen by Bdellovibrio or bacteriophages; (ii) suppression of intestinal pathogens with probiotics; (iii) reduction of environmental pathogens via probiotics, biofloc, or bivalves and fish; and (iv) blocking transmission of pathogens using predatory fish. “Shrimp‐fish polyculture” system for diseased biocontrol, which is convenient, effective, and affordable, focuses on blocking disease transmission routes. The efficacy of this strategy has been firmly established for white spot syndrome virus (WSSV). However, its application to other shrimp diseases is not widespread. Herein, a “shrimp‐fish polyculture” biocontrol plan was designed and successfully validated against Vibrio harveyi in shrimp. These findings successfully expand the application of the “shrimp‐fish polyculture” system to the control of bacterial diseases in shrimp, thereby offering new perspectives and methods for the biocontrol of diseases caused by various shrimp pathogens.

Sea Cucumber Neuropeptides: Bridging Molecular Insights Towards Aquaculture Innovations - Yingqiu Zheng; Huachen Liu; Saowaros Suwansa‐ard; Scott F. Cummins; Muyan Chen (Reviews in Aquaculture, 2026)
The sea cucumber (class Holothuroidea) holds significant commercial value due to strong global demand, especially in East and Southeast Asian markets. Overexploitation of wild stocks has thus driven aquaculture expansion; however, current culture methods remain inadequate to meet projected demand or overcome traditional practice limitations. As evolutionarily ancient endogenous bioactive molecules, neuropeptides regulate diverse physiological processes and behaviors, demonstrating great potential as eco‐friendly tools for precision sea cucumber aquaculture. Identification and functional characterization of these neuropeptides improve our understanding of their evolutionary history and facilitate their application in aquaculture practice. In this review, we summarize the diversity of known sea cucumber neuropeptides and their receptors, their engagement with downstream cellular signaling pathways, and their roles in key biological processes, including feeding and growth, reproduction, regeneration, larvae settlement and metamorphosis, and locomotion. Future research should prioritize investigating neuropeptide regulatory networks, determining their functions across developmental stages, developing large‐scale peptide production methods, and improving delivery efficiency, all of which are critical for the application of neuropeptides to achieve sustainable, eco‐friendly sea cucumber aquaculture.

Rethinking Aquaculture Resilience Beyond Species Diversification: Insights From the Lower Mekong Delta With Global Implications - Khuong V. Dinh (Reviews in Aquaculture, 2026)

Cover Image - Faisal Ahmad Lodhi; Fahim Ullah Khan; Aabid Ullah Khan; Jae‐Seong Lee; Muhammad Abbas; Hanafiah Fazhan; Khor Waiho; Menghong Hu; Youji Wang (Reviews in Aquaculture, 2026)
The cover image is based on the article Multi‐Stressor Responses in Marine Bivalves: Integrating Climate Change, Pollutants, and Microbiome Shifts for Aquaculture Resilience by Faisal Ahmad Lodhi et al., https://doi.org/10.1111/raq.70169 . image

Gonadogenesis in Farmed Bivalves: Factors Driving Sex Differentiation and Gametogenesis - Ahmed Mokrani; Chenyu Shi; Pierre Boudry; Liliana Milani; Kazue Nagasawa; Hong Yu; Qi Li; Shikai Liu (Reviews in Aquaculture, 2026)
Optimization of aquaculture output requires a thorough assessment of growth and reproductive performance in farmed fish and shellfish, as a clear understanding of the reproductive trait regulation is essential for selective breeding programs. This review aims to provide a comprehensive synthesis of gonadogenesis and its regulatory mechanisms in farmed bivalves, while highlighting key knowledge gaps that remain to be addressed. In the first section, we present an overview of germ cell and associated somatic cell development and interaction, review sex determination/differentiation, and describe the reproductive modes and gametogenic processes observed in these sessile organisms following sexual maturation. Secondly, we outline current knowledge of the mechanistic regulatory processes controlling these traits, including the roles of key genes, epigenetic control, and transcriptional regulators. Furthermore, we integrate recent molecular, cellular, and physiological findings, while critically highlighting key points where knowledge remains limited or incomplete, and where further validation and investigation are required. Finally, we summarize recent advances concerning the effect of external factors and elucidate how environmental factors such as water temperature, food availability, and chemical contaminants mechanistically affect gonadogenesis. Despite advancement and significant progress driven by hatchery technologies and sophisticated research methodologies, a comprehensive understanding of the interactions between environmental and genetic factors shaping this peculiar process remains elusive. Future research incorporating multi‐omics approaches holds great promise for disentangling the genetic and regulatory architecture underlying gonadogenesis in these organisms, hence improving aquaculture production and breeding programs.

From Barriers to Breakthroughs: Toward Sustainable Artificial Reproduction in the Japanese Eel ( Anguilla japonica ) - Jincan Chen; Yilei Wang; Ziping Zhang; Yonghua Jiang (Reviews in Aquaculture, 2026)
The Japanese eel ( Anguilla japonica ) displays a uniquely complex reproductive strategy shaped by its catadromous life cycle, protracted maturation, and extreme sensitivity to environmental cues. Despite decades of research, key regulatory mechanisms governing its reproduction remain unresolved. This review first establishes the biological and ecological foundations of the Japanese eel reproduction, then examines major biological and technical barriers to successful captive breeding, followed by an integration of current knowledge on neuroendocrine control, pathways of sex differentiation, and the physiological and molecular bases of artificial maturation. Emphasis is placed on both established mechanisms and emerging hypotheses, with particular attention to their implications for aquaculture. By identifying critical knowledge gaps, we highlight priorities for future research essential to both species conservation and the development of sustainable breeding technologies. These insights provide a foundation for optimizing hormonal induction protocols, improving larval performance, and refining nutritional management across life stages, particularly for broodstock conditioning and early larval development, thereby enabling more reliable and scalable closed‐cycle aquaculture for Japanese eel.

Dietary Supplements and Biological Performance in Abalone: A Systematic Evidence Map - Rebecca L. Pedler; Matthew S. Bansemer; James O. Harris; Ondi L. Crino; Malgorzata Lagisz (Reviews in Aquaculture, 2026)
Abalone in the genus Haliotis are economically important for aquaculture. Abalone naturally graze on macroalgae; however, they are increasingly fed formulated pellets that lack essential nutrients in aquaculture. Dietary supplements may increase abalone growth performance, immunity, survival, and market traits. Despite these advantages, there has been limited industry uptake, which can be influenced by a lack of formal evidence synthesis on the topic. Here, we provide the first systematic evidence map summarizing global research on the effects of dietary supplements on biological performance in abalone, based on 143 studies meeting inclusion criteria. China‐affiliated researchers authored most articles while Australia and New Zealand had disproportionately high, and South Korea disproportionately low contribution relative to production, which may have been influenced by indexing and linguistic restrictions. Algal and/or diatom meals were the most tested dietary supplements (19.6%), with most efforts focused on Ulva spp. supplementation. Vitamins were also intensively researched (18.2%), with emphasis on those that are water soluble. Growth performance and survival were the most frequently assessed outcomes (72.0% and 58.0% respectively). Consumer‐focused traits, such as sensory attributes and abalone colour, were measured by less than 10% of articles, suggesting a bias toward production‐centric outcomes. No studies provided raw data, source code, or pre‐registered protocols, and future abalone research should adopt best practices for data credibility. Our map provides direction for future empirical studies and meta‐analyses by highlighting research trends, gaps, and evidence clusters, which will assist in greater translation of research on dietary supplements to the abalone industry.

Life Cycle Assessments of Bivalve Aquaculture: A Systematic Review and Meta‐Analysis - Mausam Budhathoki; Stephanie Horn; Sujita Pandey; Manali Chakraborty; Daniel Taylor; Richard Newton; Per Dolmer; Marianne Thomsen (Reviews in Aquaculture, 2026)
Bivalve aquaculture is generally considered a low‐impact food system with ecosystem co‐benefits. Yet its net contributions to climate change (CC), eutrophication (E), and broader ecosystem stewardship remain uncertain. To address this, we analyzed 31 life cycle assessment studies of bivalve farming. Reported impacts varied substantially. Median values were 385 kg CO 2 ‐eq t −1 for CC (interquartile range [IQR]: 164–612.2), 0.25 kg PO 4 3− ‐eq t −1 for E (IQR: 0.15–0.49), 0.014 kg N‐eq t −1 for marine eutrophication (ME) (IQR: 0.00–0.50), 1.86 kg SO 2 ‐eq t −1 for acidification (A) (IQR: 0.56–6.26), and 10,772 MJ t −1 for energy demand (ED) (IQR: 7231–16,383). High‐impact processes were mainly linked to electricity and fuel use, plastic infrastructure, and transport. Reported co‐benefits included nutrient removal and potential carbon storage in shells. Regression analysis showed that methodological choices influenced CC and ME, whereas species differences were significant only for ME. Meta‐analysis revealed high heterogeneity across studies ( I 2 = 90% for CC and 85% for E). Distinct species patterns emerged. Mussels showed lower CC but variable E outcomes. Oysters showed moderate CC but relatively higher E burdens. Clam showed more variable results and was sensitive to carbon accounting assumptions. Accounting for shell carbon sequestration influenced CC but had little effect on E. Overall, bivalve aquaculture shows variability across studies. Outcomes are strongly influenced by methodological choices and species differences. Claims of climate neutrality remain sensitive to methodology and should be evaluated alongside nutrient trade‐offs. Standardized methods and broader geographic coverage are needed for robust sustainability assessments and comparisons.

Agro‐Leadership Model in the Aquaculture Sector in Mexico - Antonia Terán‐Bustamante; Antonieta Martínez‐Velasco; Evelia López‐Meza (Reviews in Aquaculture, 2026)
This research aims to analyze leadership for innovation in the Mexican aquaculture sector. The main characteristics of aquaculture producers in the Mezquital Valley of Hidalgo State have been identified and grouped according to an Agro‐leadership profile. The methodological strategy uses machine learning techniques. The data were obtained from a questionnaire of 40 owners or representatives of aquaculture farms. The results show that most leaders with the characteristics of the Agro‐leadership model directly influence innovative products, processes, managers, and marketing. According to the developed model, the most relevant factors are seeking solutions to problems, leadership grounded in personal values, establishing connections among leaders, and providing opportunities for others' personal and professional development. These results provide empirical evidence for decision‐making, both for entrepreneurs in the sector seeking to strengthen their innovation capacity and for public policymakers designing targeted support programs, by highlighting the fundamental role of values‐based leadership and collaborative networks in transforming aquaculture practices.

Emerging Viruses in Decapod Crustaceans: A Global Review - Xuan Dong; Guohao Wang; Kejun Wang; Kaisong Zhang; Hua Xu; Liying Wang; Xuan Li; Liang Qiu; Win Surachetpong; Jing Wang; Jee Eun Han; Kathy F. J. Tang; et al. (Reviews in Aquaculture, 2026)
Due to its advantages of a short production cycle, wide market demand, and profitability, decapod crustacean aquaculture has become one of the fastest‐growing food production systems. However, disease outbreaks have become one of the most important factors limiting the sustainability of decapod crustaceans. This review synthesizes current advancements in the understanding of emerging viral pathogens in decapod crustacean aquaculture, with emphasis on their genomic‐based taxonomical classification, susceptible hosts, global distribution, clinical manifestations, pathogenic mechanisms, diagnostic developments, and management strategies. This paper summarizes details of emerging viruses with confirmed pathogenicity (such as decapod iridescent virus 1), as well as viruses with uncertain or yet‐unconfirmed pathogenic roles. In addition, we highlight the role of next‐generation sequencing in virus discovery and examine the challenges posed by coinfection with other microorganisms. This review provides information to help the decapod crustacean aquaculture industry in setting up early warning systems to prevent the introduction of emerging pathogens into the production systems.

Does Size Grading Improve Fish Farming? Evidence From a Meta‐Analysis - Chenchen Wu; Ze Zhu; Yanci Wen; Songming Zhu; Ying Liu; Kai Liu; Yi‐Jia Shih; Zhangying Ye; Xingguo Liu; Jian Zhao (Reviews in Aquaculture, 2026)
Size grading, sorting a cohort into more homogeneous size classes, is widely used in aquaculture and presumed to enhance production efficiency. However, reported effects on fish growth are inconsistent. To address this uncertainty, we conducted a comprehensive meta‐analysis spanning 32 species to systematically evaluate the effect of size grading on fish growth and to identify key moderators of this effect. Overall, size grading reduced the average specific growth rate (SGR) by 4.50%. Species personality type (aggressive vs. docile) was the most important among the moderators tested: grading significantly reduced average SGR in docile species but had no effect in aggressive ones; and in both aggressive and docile species, the effect of grading depended positively on the initial variation coefficient (IVC). We emphasized that aggressive behaviour is closely associated with the effects above and pointed out the role of IVC between frequency of aggressive behaviour (FAB) and daily food intake (DFI) in aggressive species. We also found size grading had opposing effects on changes in size heterogeneity, which is beneficial for aggressive but not docile species. Besides, while size grading significantly reduced cannibalism rate (CR) in both personality types, it was at the cost of overall SGR. Therefore, size grading may not be advisable for docile species due to growth suppression. For aggressive species, size grading generally reduces overall production, but it is recommended from an individual quality standpoint, provided a moderate size heterogeneity is maintained.

Tracing a Decade of Tilapia Lake Virus Research: Breakthroughs, Challenges, and Projections - Dorothea V. Megarani; Christopher J. Martyniuk; Roy P. E. Yanong; Felipe Pierezan; Win Surachetpong; Kuttichantran Subramaniam (Reviews in Aquaculture, 2026)
Tilapia are one of the most farmed fish groups worldwide, with global production exceeding 6.55 million tons in 2022, generating an estimated market value of approximately USD 20.9 billion. Tilapia are favored for their fast growth rate, adaptability to various farming environments, and high nutritional value as a protein source. However, the tilapia industry has encountered a significant challenge with the emergence of tilapia lake virus (TiLV), first noted in 2014. This highly contagious virus has the potential to devastate tilapia populations, leading to substantial economic losses and raising serious concerns about food security in countries reliant on this fish for livelihoods and sustenance. The rapid spread of TiLV and its significant impact on the tilapia industry have led to widespread concerns among stakeholders, researchers, and policymakers. In response, there has been an increasing focus on research and development of effective strategies to control and manage TiLV infections. This review paper aims to provide a comprehensive overview of the substantial advancements in the understanding of TiLV, delving into its genetic variation and manipulation, molecular pathogenesis, epidemiology, transmission pathways, clinical signs, diagnosis, and the underlying pathogenesis of the virus. Additionally, we summarize the current knowledge on the potential impact of TiLV on the global tilapia industry and the measures being implemented to control its spread. Finally, we discuss ongoing scientific efforts toward the development of vaccines and other innovative strategies for effectively managing TiLV infections, highlighting the importance of continued research to secure the future of tilapia aquaculture on a global scale.

Elucidating the Immunological Basis of Large Yellow Croaker Larimichthys crocea Offers New Strategies for Its Disease Management - Yinnan Mu; Weini Zhang; Pan Qin; Wenxing Li; Zhengwei Cui; Yang Ding; Jingqun Ao; Jiangtao Gao; Xinhua Chen (Reviews in Aquaculture, 2026)
Large yellow croaker Larimichthys crocea is a major mariculture species in China, achieving an annual yield of 292,615 tons by 2024. Commercial production faces considerable challenges from disease outbreaks, necessitating comprehensive immune mechanism research. Through comprehensive genomic and transcriptomic investigations, scientists have identified distinguishing characteristics within the L. crocea immune system, encompassing robust innate defense mechanisms, marked by the expansion of pattern recognition receptor lineages, antimicrobial peptide gene families, and antiviral defense‐related genes, and well‐developed adaptive immune capabilities. The current review outlines the molecular foundations underlying immune responses in L. crocea , highlighting the cooperative interplay between innate and adaptive defense systems when confronting pathogenic threats and environmental fluctuations. It bridges basic scientific inquiry with practical aquaculture implementation, exploring disease control strategies. Available evidence indicates possibilities for strengthening disease resistance through precision immunomodulation and improved aquaculture methods. Priority research areas encompass elucidating host‐pathogen relationships and establishing practical disease prevention protocols for industrial‐scale operations.

Toward Sustainable Rainbow Trout Lipid Nutrition: A Systematic Review of Lipid Optimization Strategies in Controlled Conditions - Rosendo L. Azcuy; Alejandro Villasante; Susana Perelman; Matías E. Casaretto; Patricio Dantagnan; Gabriel A. Morales; Stefanie Colombo (Reviews in Aquaculture, 2026)
Replacing fish oil (FO) in feeds remains a challenge for aquaculture sustainability. While experimental studies have evaluated the effects of alternative lipids on fillet long‐chain polyunsaturated fatty acids (LC‐PUFA) in rainbow trout, a quantitative synthesis of these effects is lacking. Here, 119 experimental diets from 29 controlled studies were synthesized through a statistical framework combining linear mixed‐effects models (LMM), generalized additive models (GAM), and leave‐one‐study‐out validation. Dietary docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) consistently predicted fillet DHA and EPA concentrations, independent of growth rate and not significantly influenced by temperature or lipid level. While growth performance was unaffected by FO replacement, LC‐PUFA deposition was not equivalent across lipid origins: FO and vegetable‐based diets supported steeper diet‐to‐fillet transfer slopes compared to animal‐derived lipids. GAMs revealed non‐linear thresholds, with active deposition occurring only when dietary LC‐PUFA exceeded near 10 mg g −1 and the dietary n‐6:n‐3 ratio remained below approximately 4. Temperature, modelled linearly, showed no significant effect on fillet LC‐PUFA deposition within the analysed dataset. These results demonstrate that FO can be reduced without compromising growth, but not without reformulating LC‐PUFA supply and precursor balance. Successful FO replacement is therefore a formulation problem rather than an ingredient substitution issue. Emerging sources such as algal oils or engineered oilseeds represent a viable pathway toward sustainable feeds delivering nutritionally valuable fillets. The identified dietary thresholds provide practical guidance for feed formulation by defining minimum LC‐PUFA inclusion levels and n‐6:n‐3 ratios required to achieve target fillet EPA and DHA concentrations under controlled temperature conditions.

Multi‐Stressor Responses in Marine Bivalves: Integrating Climate Change, Pollutants, and Microbiome Shifts for Aquaculture Resilience - Faisal Ahmad Lodhi; Fahim Ullah Khan; Aabid Ullah Khan; Jae‐Seong Lee; Muhammad Abbas; Hanafiah Fazhan; Khor Waiho; Menghong Hu; Youji Wang (Reviews in Aquaculture, 2026)
Marine bivalves play pivotal ecological and economic roles but are increasingly challenged by multiple environmental stressors. Although there is extensive research on the effects of individual stressors, a comprehensive review is needed to synthesize current evidence and clarify how multiple interacting stressors collectively affect the physiology and resilience of marine bivalves. This review integrates evidence from 2010 to 2025, encompassing 178 peer‐reviewed studies emphasizing the combined and interactive impacts of climate change drivers (warming, hypoxia, salinity, and ocean acidification), pollutants (heavy metals, persistent organic pollutants, endocrine‐disrupting chemicals, antibiotics, nanoparticles, microplastics), and microbiome shifts on future aquaculture resilience. Literature was systematically retrieved from Web of Science, Scopus, PubMed, and Google Scholar in accordance with PRISMA 2020 guidelines. Bibliometric mapping (VOSviewer 1.6.20) revealed a rapid growth in research after 2018, characterized by studies on Mytilus , Crassostrea , and Ruditapes . A systematic evaluation of recent evidence was conducted, combining data from physiological, molecular, and microbial studies, with particular attention to implications for aquaculture. The analysis reveals that stressors rarely act alone. Instead, their cumulative and interactive effects cause oxidative stress, disrupted energy allocation, destabilized host‐microbe relationships, lowered tolerance thresholds, and other eco‐physiological consequences. These results highlight the vulnerability of bivalve populations to rapid coastal urbanization, declining water quality, and sediment contamination. The review concludes that resilience can be enhanced through selective breeding for stress‐tolerant genotypes, integrated monitoring of pollutants and microbial indicators, and multi‐omics approaches to guide adaptive aquaculture management.

Epigenetic Plasticity of Fish Pigmentation Under Environmental Stress: A Gene–Environment–Epigenetic Interaction Model - Rabia Tahir; Songlin Cai; Samra; Fozia Afzal; Jinliang Hou; Lingxiao Wang; Ayesha Arif; Mohamed Aboraya; Zhiyi Zhang; Jing Ke; Xin Hou; Jun Wang; et al. (Reviews in Aquaculture, 2026)
Fish pigmentation exhibits remarkable plasticity, enabling rapid and long‐term phenotypic adjustments in response to environmental stressors. We propose a gene–environment–epigenetic (G × E × Ep) interaction model that integrates environmental cues, neuroendocrine signaling, and multilayered epigenetic regulation to explain dynamic pigmentation outcomes. Key mechanisms, including DNA methylation, histone modifications, chromatin remodeling, and non‐coding RNAs, modulate pigment cell differentiation, distribution, and patterning in a context‐dependent manner, while involving α‐melanocyte–stimulating hormone (α‐MSH), melanocyte‐concentrating hormone (MCH), and adrenocorticotropic hormone (ACTH) to relay environmental signals to epigenetic machinery. Emerging genome‐wide and single‐cell epigenomic approaches, together with CRISPR/dCas9‐based epigenome editing, now enable precise mapping and functional validation of these pathways. Adaptive pigmentation enhances ecological fitness, but environmental stress can trigger maladaptive, potentially heritable changes. Importantly, integrating epigenetic knowledge with husbandry practices offers actionable strategies to rescue or stabilize pigmentation under stress, such as environmental modulation, dietary supplementation, and targeted broodstock selection. We identify critical gaps regarding the stability, tissue specificity, and transgenerational inheritance of epigenetic marks and propose a roadmap for applying multilayered epigenomic insights to sustainable aquaculture, ornamental fish management, and climate‐resilient breeding programs.

From Oligotrophic to Hypertrophic: A Trophic‐State Analogy for Classifying Aquaponic and Bioponic Systems - Ranka Junge (Reviews in Aquaculture, 2026)

Industry Development and Diseases in the Norwegian Salmon Aquaculture Industry - Frank Asche; Bård Misund; Tonje Osmundsen; Cecilie S. Walde; Edgar Brun; Mattew DiMaggio; Taryn M. Garlock; Brit Hjeltnes; Marit S. Olsen; Ragnar Tveteras (Reviews in Aquaculture, 2026)
Norwegian salmon aquaculture production has grown rapidly since the 1970s. Accompanying the growing production have been a number of disease challenges of which at least two of the outbreaks threatened the industry's existence. The challenges caused by disease may appear to become more serious as the number of diseases being diagnosed and measures taken by the companies and regulators to manage disease increase. We will review the development of the industry and how diseases have impacted economic viability, the impact of the most important diseases and their control measures as well as the development of the governance and regulatory system in relation to disease. Despite the many disease challenges faced by the industry, we will argue that it has never been in a better position to address these issues and the disease cost per kilo of fish has most likely never been lower. When the industry originated in the 1970s, the knowledge with respect to disease in relation to salmon, such as how to diagnose, prevent or control them, was highly limited. The growth of the industry created a corresponding demand for veterinary knowledge and services, and these have been rapidly growing alongside the industry. This veterinary capacity facilitates the identification of new diseases and the development of novel control measures created with increasing efficiency. However, challenges with diseases will persist, as in all biological production processes, as it is normally not economically optimal to eradicate any disease if this is possible at all.

The Roles of SOCS in Teleost Immunity: Cytokine Regulation and Host Defense - Ying Zhang; Li Yang; Xiuying Cui; Feng Gao; Yanjing Zhao; Xianghui Kong (Reviews in Aquaculture, 2026)
The Suppressor of Cytokine Signaling (SOCS) family comprises key regulatory molecules which are essential for maintaining immune homeostasis in vertebrates. Owing to a teleost‐specific whole‐genome duplication event, SOCS family members exhibit higher diversity and significant functional differentiation, forming a complex and precise immune regulatory network. This review comprehensively summarizes the current understanding of SOCS‐mediated cytokine regulation and host defense mechanisms in teleosts. SOCS proteins, particularly SOCS1 and SOCS3, exert dual regulatory effects in antiviral and antibacterial immunity as well as in inflammatory balance by negatively modulating key pathways such as JAK/STAT and NF‐κB, exemplifying their “double‐edged sword” role. Moreover, we provide the first comprehensive synthesis of environmental regulation of SOCS expression in teleosts, integrating emerging evidence on how to modulate SOCS levels after temperature stress, neuroendocrine activation via cortisol, hypoxia, and chemical pollutants and how to link environmental conditions to immune competence. This environmental perspective supplies direct implications for understanding stress‐induced immunosuppression in aquaculture. Finally, we discuss the potential application of targeting SOCS signaling in aquaculture practices, including applications in disease‐resistant breeding, vaccine development, and immunostimulant design. In‐depth understanding of SOCS diversity and function in fish will provide novel molecular insights and innovative strategies for precise disease control and sustainable aquaculture.

Aquaculture Gamete Update: A Virtual Special Issue - Deepali Rahi Roy (Reviews in Aquaculture, 2026)
Aquaculture relies heavily on the controlled reproduction of aquatic species, making gametes—sperm and egg—an inevitable part of a successful breeding program. This virtual special issue compiles 45 articles published between 2009 and the present that collectively advance our understanding of gamete production, quality, availability, preservation, and manipulation in aquaculture species. The issue aims to assemble fragmented knowledge on functional biology, preservation techniques, and molecular mechanisms while bridging knowledge gaps across diverse taxa. To provide a coherent framework, the selected articles are divided into three major themes addressing fundamental concepts, recent advances, challenges, and future perspectives.

Harnessing Indonesian Seaweed Biodiversity: A Comprehensive Two‐Decade Review of Cultivation, Bioactive Compounds, and Applications - Kasmiati Kasmiati; Ade Wahyul Fajri Alimin; Fatchurrachman Fatchurrachman; Jamaluddin Fitrah Alam; Syahrul Syahrul; Aswin Aswin; Fahrurrozi Fahrurrozi; Dedy Muhammad Iqbal; Mella Sarah Elmania (New Zealand Journal of Marine and Freshwater Research, 2026)
Indonesia is home to a high diversity of seaweeds, encompassing both wild and cultivated species. Over the past two decades, seaweed aquaculture production has increased 23‐fold, primarily driven by the eastern regions of the archipelago. This review systematically synthesizes two decades of research and development efforts, focusing on cultivation practices, the diversity of bioactive compounds isolated from Indonesian seaweeds, and their broad applications. It also evaluates literature and production data, highlighting the remarkable potential of Indonesian seaweeds as sources of bioactive components such as peptides, pigments, polyphenols, and polysaccharides, offering various health benefits, including antioxidant, anti‐inflammatory, anticancer, and antiviral properties. Furthermore, the review explores the potential use of seaweed across sectors, including animal feed, agriculture, cosmetics, and food, while specifically addressing the dynamics of carrageenan production in Indonesia‐currently the world's largest producer of carrageenan seaweed. Nonetheless, several challenges remain, particularly regarding sustainable farming practices, efficient bioprospecting, value chain development, and scalability of industrial applications. Addressing these issues is essential to ensure the long‐term viability and competitiveness of Indonesia's seaweed industry. This review underscores the strategic importance of integrating biodiversity utilization with biotechnological and industrial innovation to unlock the full socioeconomic and environmental potential of Indonesia's seaweed resources.

Selective Breeding and Production Strategies to Support Snapper Farming in the Warming Waters of New Zealand's South Island - Georgia Samuels; Flavio Ribeiro; David Ashton; Sharon Ford; Joshua Fantham; Julie Blommaert; Damian Moran; Maren Wellenreuther (New Zealand Journal of Marine and Freshwater Research, 2026)
Diversifying aquaculture species is essential for building resilience in the face of climate change, particularly as warming oceans challenge existing production systems. In New Zealand's Marlborough Sounds, rising sea temperatures are making finfish (e.g. salmon) farming increasingly difficult, highlighting the need for climate‐adapted alternatives. This study evaluated the aquaculture performance of growth‐selected F 4 versus unselected F 1 Australasian snapper ( Chrysophrys auratus ) across two rearing environments: sea pens in the Marlborough Sounds and a land‐based system in Nelson. ≈1000 F 4 and 1000 F 1 snapper were reared from 4 to 30 months of age in each system. At 30 months, selectively bred snapper showed improved growth—body length increased by 1.7% (land‐based) and 4.8% (ocean‐based) and body weight by 9.8% and 14.2%, respectively—compared with F 1 snapper. Survival was also significantly higher, with selected snapper outperforming unselected snapper by 84.2% in the land‐based and 60.8% in the ocean‐based system. Mortality peaked in the first winter across both systems, with size‐selective patterns in sea pens informing minimum stocking sizes. These findings offer important insights for refining husbandry and selective breeding practices. They are not only relevant for New Zealand but also for global aquaculture sectors seeking robust species suited to changing marine environments.

Reduction in Suspended Sediment Loads Following Canopy Closure: The Impact of Pasture‐To‐Pine Plantation ( P.radiata ) Conversion in a Headwater Catchment - Andrew O. Hughes; Thanh D. Dang (New Zealand Journal of Marine and Freshwater Research, 2026)
Plantation forestry is an important land use in New Zealand (currently 7% of the area), and recent central government incentives for tree planting will likely result in further increases in the future. Plantation forestry in New Zealand often occurs on steep, high‐erodible land, often as a form of catchment restoration and/or erosion control. However, the potential for episodically high erosion and impacts on waters during tree harvest is a concern. We studied suspended sediment loads (SSLs) from the originally grazed pasture Mangaotama headwater catchment, which was partially converted to a pine plantation, over 31 years (encompassing almost a complete rotation) within a BACI (before‐after‐control‐impact) design. Suspended sediment sampling in both the impact catchment and a nearby control (the native‐forested Whakakai Catchment) was used to prepare sediment ratings for flow. We show that the SSLs within the Mangaotama catchment decreased by a factor of three in response to increasing forest cover (mostly P. radiata plantation) from ~2% to ~62% of the catchment. The establishment of plantation forest may have resulted in some reduction in SSLs shortly after livestock exclusion and planting, but the most significant reduction occurred after canopy closure (~8 years after planting). This post‐canopy closure SSL reduction was a response to reduced frequency and magnitude of flow events, particularly large events which transport most suspended particular material (SPM). We estimate that a full 28‐year rotation of P. radiata ( including harvest) would export ~30% less SPM than the same catchment under grazed pasture over the same time period. Given the scarcity of such empirical evidence from New Zealand catchments, these findings should usefully inform the debate around the environmental ramifications of converting pastoral land to plantation forestry.

Post‐Thawing Viability of the Microalgae Scenedesmus dimorphus : The Importance of Species‐Specific Cryopreservation - Martha Prieto‐Guevara; César Jiménez‐Velásquez; Yamid Hernández‐Julio; José Espinosa‐Araujo; Víctor Atencio‐García (New Zealand Journal of Marine and Freshwater Research, 2026)
Cryopreservation of microalgae is crucial for preserving strains that are valuable for biotechnology and industry. The cryopreservation of Scenedesmus dimorphus is particularly relevant due to its emerging role in sustainable biotechnology, including its high lipid accumulation for biofuel production, adaptability to variable lighting conditions, and potential for biomass generation in large‐scale photobioreactors. This study evaluates the response of S. dimorphus to two common cryoprotectants, dimethyl sulfoxide (DMSO) and methanol (MeOH), used at concentrations of 5% and 10%. Cell viability post‐thaw was assessed through three criteria: no cell damage (NCD), cell damage (CD), and marked lesions (ML), with flow cytometry to measure damage to mitochondria and cell membranes. The study followed a 2 × 2 factorial design with five replications per treatment, evaluating population growth and CD from the fifth day post‐thaw. Findings indicated that methanol (MET) at 5% or 10% supported moderate population growth, suggesting it as a potential alternative for cryopreservation in S. dimorphus . However, S. dimorphus showed greater susceptibility to CD and lesions than other species in the same genus, highlighting the need for species‐specific protocols to optimize post‐thaw viability. This research underscores the importance of tailored cryopreservation strategies for different microalgae species.

Commentary: Trends and Tensions in Freshwater and Fisheries Management in Central Otago, New Zealand - Harvey C. Perkins; Niall R. N. Watson (New Zealand Journal of Marine and Freshwater Research, 2026)
Recent resource management planning processes and decisions in Central Otago, New Zealand, illustrate changes in policy direction for freshwater management. These processes and decisions also highlight interactions between, and values associated with, indigenous and introduced sports fish. We assess the outcomes of resource management planning decisions on four river catchments in Central Otago: Nevis, Kye Burn, Lindis and Manuherekia—all of which have been controversial—and comment on environmental protection, water allocation outcomes and subsequent management activities, including those associated with freshwater fisheries, outdoor recreation and regional economic development. We position our discussion in a context of rapid regional economic, social and population change and conclude by emphasising that because of this change, there is a likelihood of increasing complexity in perspectives on freshwater and sustained future political contest over the directions of freshwater management in Central Otago.

The Effects of Oxidized Fish Oil on Growth Performance, Body Composition, and Intestine Histology of Nile Tilapia ( Oreochromis niloticus ) Fingerlings - Sana Yagoub Abdallah Tahir; Aysun KOP (New Zealand Journal of Marine and Freshwater Research, 2026)
Fish oil is a major source of energy and essential fatty acids for farmed fish; however, it is highly susceptible to oxidation during storage. This study aimed to evaluate the effects of oxidized anchovy oil on growth performance, body composition, and intestinal histology of Nile tilapia ( Oreochromis niloticus ) fingerlings. Juvenile fish with an initial mean body weight of 15.07 ± 0.58 g were randomly stocked into nine fiberglass tanks, with three dietary treatment groups and a stocking density of 50 fish per tank. Experimental diets were prepared using fish oil with varying peroxide values: fresh oil (4.95 meq/kg) for the control group, and oxidized oil (50 and 100 meq/kg) for the second and third treatment groups, respectively. All diets were formulated to be isoproteic (35% crude protein) and isolipidic (8% crude lipid), and fish were fed at 3% of body biomass. Results indicated that fish fed with fresh anchovy oil exhibited significantly higher growth rates, increased body protein and unsaturated fatty acid content, and normal intestinal morphology compared to fish fed oxidized oil. In conclusion, the inclusion of oxidized fish oil negatively impacted growth performance, body composition, and gut histology in O. niloticus fingerlings.

Bacterial Microbiome Composition and Functional Potentials Across Digestive Regions of Wild New Zealand Abalone ( Haliotis iris ) - Jinchen Guo; Andrea C. Alfaro; Leonie Venter; Donnabella C. Lacap‐Bugler (New Zealand Journal of Marine and Freshwater Research, 2026)
Abalone are valuable commercial marine gastropods, supporting both aquaculture and fishery markets. An important ecological aspect of their survival and physiological performance in a given habitat is a complex and balanced symbiotic relationship with microbes in their digestive system. 16S rRNA Illumina MiSeq sequencing was used to investigate the microbial composition of New Zealand abalone ( Haliotis iris ) digestive regions (buccal cavity, foregut, and hindgut), seaweed, and sediment samples from the Cook Strait, New Zealand. The findings revealed an overlap in the microbial communities in the foregut and hindgut samples which differed from buccal cavity samples. The foregut and hindgut were dominated by Fusobacteria, Firmicutes, and Proteobacteria. Proteobacteria were abundant in the buccal cavity, seaweed, and sediment samples. Despite distinct overall microbial compositions in the abalone digestive tract and environmental samples (seaweed and sediment), observed overlaps in bacterial richness and diversity suggest that surrounding habitats may serve as significant reservoirs for the abalone gut microbiome, reflecting potential microbial exchange and microbial functional adaptions. Establishing this microbial baseline for wild H. iris provides a reference for detecting microbiome shifts associated with environmental stress, dietary changes, and supports the development of microbiome‐targeted feeds that can be used to enhance abalone growth in an aquaculture setting.

Finding the Best Nursery: How Habitat Features Shape Juvenile Snapper ( Chrysophrys auratus ) Density - Jessica L. Campbell; Richard B. Taylor; Mark A. Morrison (New Zealand Journal of Marine and Freshwater Research, 2026)
This study examines habitat preferences of juvenile Australasian snapper ( Chrysophrys auratus ) in northeastern New Zealand, analysing data from 113 stations across structured and unstructured habitats. We investigated how juvenile snapper densities were influenced by environmental factors, including prey availability and physical habitat features. Seagrass supported significantly higher snapper densities than all other habitats, with mean densities more than 80 times greater than non‐seagrass habitats, reinforcing its role as a key nursery habitat. Regression analyses identified seagrass presence as the strongest predictor of density, with benthic productivity and plankton flux also weakly correlated when considering all habitats together. In non‐seagrass environments, there were weak trends for densities to be higher in shallow water and in the presence of burrows. Current speed also appeared to play a role, potentially modifying prey availability and interacting with habitat structure. These findings provide new insights into why seagrass meadows are particularly beneficial for juvenile snapper, reinforcing the need for targeted conservation and restoration efforts to sustain nursery habitats and support snapper populations.

In Situ and Remote Observation of Baroclinic Waves, Mixing Processes, and Circulation in Lake Taupō, Aotearoa/New Zealand - Max Gibbs; Mat Allan; Aidin Jabbari (New Zealand Journal of Marine and Freshwater Research, 2026)
Mixing processes in Lake Taupō are driven largely by wind stress that can generate barotropic (surface) and baroclinic (internal) waves. During a 2002 study, a baroclinic wave in the southern basin of Lake Taupō had a setup amplitude greater than 45 m, resulting in upwelling at the southern end of the lake following strong west/southwest winds. Vessel‐mounted acoustic Doppler current profiler data showed that this setup wave was associated with southward near‐shore currents exceeding 40 cm s −1 at 20 m depth. We postulate that these are upwelling subsurface return currents occurring in Lake Taupō following major setup events, which may subsequently trigger the formation of Kelvin waves within the lake. Observations from 2002 also suggest that the return current advected phytoplankton from the deep chlorophyll maxima in the northern basin into the southern basin, resulting in nongrowth increases in phytoplankton concentrations due to phytoplankton focusing. In another event in 2004, the sediment plume from an extreme flood exhibited a gyre‐like form in the lake, driven by wind‐induced surface currents. These observations highlight the dynamic interplay between wind forcing, internal wave activity, and basin‐scale circulation in Lake Taupō, with important implications for nutrient transport, sediment dynamics, and ecosystem structure.

High Accuracy Dissolved Oxygen Prediction in Water Quality Analysis with A‐XG‐Q Hybrid Model - Yıldırım Özüpak; Feyyaz Alpsalaz; Emrah Aslan; Hasan Uzel (New Zealand Journal of Marine and Freshwater Research, 2026)
This study presents A‐XG‐Q, a groundbreaking hybrid model for predicting dissolved oxygen (DO) levels in water quality analysis that integrates ARIMA, XGBoost, and QAOA. ARIMA captures linear trends and seasonal patterns, XGBoost models complex nonlinear relationships, and QAOA optimizes hyperparameters such as learning rate and tree depth for computational efficiency. Using a Kaggle dataset spanning 1989–2019, the model achieved an R 2 of 0.990 and an RMSE of 0.050 despite missing data (36% DO, 96% air temperature), demonstrating exceptional accuracy. Temporal analyses revealed seasonal variations in DO and temperature, while Secchi depth and water depth remained stable. Correlation analysis identified a negative DO‐water temperature relationship, providing ecological insights. QAOA optimization reduced training time, enabling real‐time monitoring applications. By combining classical statistical methods, advanced machine learning, and quantum optimization, A‐XG‐Q outperforms many hybrid models and effectively handles data variability and missing values. This work advances environmental data science by providing a robust framework for sustainable water resource management and informed policy making, with potential for broader applications in ecosystem monitoring and environmental forecasting. The model's high performance underscores its value in addressing complex environmental challenges and supporting sustainable development goals.

The Devil is in the Detail: Photo‐Identification Reveals Novel Information on the Biology of a Temperate Reef Fish, the Southern Blue Devil ( Paraplesiops meleagris ) - Simon Bryars; Jamie Hicks; Dan Easton; Craig Meakin; David Miller; Danny Brock (New Zealand Journal of Marine and Freshwater Research, 2026)
A photo‐identification technique based on the unique detail of the head markings of individual fish was developed and utilised in a long‐term (>10 years) study at four discrete populations of the southern blue devil ( Paraplesiops meleagris ), a small demersal fish endemic to Australia's Great Southern Reef (GSR). The study revealed novel information on its life history and behaviour, including that population sizes were relatively small and dominated by larger fish, juvenile recruitment was infrequent and the larger fish displayed relatively slow growth rates, longevity, high site fidelity, territorial behaviour and small home ranges. Several fish were photo‐recaptured after 14 years with one fish after 18 years. Breeding occurred during the Austral summer, whereby an adhesive egg mass was laid on the ceiling of a cave or ledge and guarded by the male until the eggs hatched into free swimming planktonic larvae. Paraplesiops meleagris has a combination of life history and behavioural traits which renders it vulnerable to localised population depletions from which it may take a long time to recover. These traits also mean that no‐take marine protected areas will be an effective conservation tool and that it could be a sentinel species for monitoring changes in the GSR.

Review About the Biodiversity of Pill Clams (Bivalvia, Sphaeriidae) in the Confines of the World, the Argentinean Patagonia - Santiago H. Torres; Micaela de Lucía; Juan P. Martin; Gustavo Darrigran; Diego E. Gutiérrez Gregoric (New Zealand Journal of Marine and Freshwater Research, 2026)
This study aims at updating the diversity and distribution of Sphaeriidae in Argentine Patagonia, with a particular emphasis on the Santa Cruz Province. Samples were collected between 2015 and 2023 across diverse habitats, including rivers, lakes, lagoons, and Patagonian wetlands, and this was complemented by data obtained from a comprehensive literature review and a revision and improvement of major malacological collections. Both manual and sieve‐based collection methods were used to obtain specimens from different habitats. From 121 records analyzed, 101 records were identified to species level, including four species of Pisidium and two of Sphaerium . Pisidium magellanicum and Pisidium patagonicum were the most frequently recorded species. Sphaerium patagonicum demonstrated the broadest distribution, ranging from northern Neuquén to southern Tierra del Fuego. Santa Cruz Province had the highest number of records (57), followed by Chubut (24), with Río Negro and Tierra del Fuego having the fewest records. We report the first record of Pisidium chilense in Neuquén Province, providing new evidence of its presence in Argentine Patagonia. These findings advance our knowledge of Sphaeriidae distribution in Patagonia and highlight gaps in coverage, particularly in less‐sampled regions.

Towards Holistic, Justice‐Oriented, and Coordinated Freshwater Fish Science and Governance in Aotearoa New Zealand - Joanne Clapcott; Marc Tadaki; Robin Holmes; Vanessa Tipoki; Carly O’Connor; Jane Kitson (New Zealand Journal of Marine and Freshwater Research, 2026)
Aotearoa New Zealand faces accelerating loss of freshwater fish biodiversity and growing pressures on culturally significant fisheries. Technical solutions alone have failed because the challenge is not only ecological, but also institutional, cultural, and relational. Change is needed across policy, research, and practice to drive better outcomes for freshwater fish, beginning with how science is conceived and undertaken. Drawing on the Fish Futures five‐year transdisciplinary research programme, we outline how a transformative research approach—focused on strengthening relationships between people and freshwater fish—responds to fragmented and justice‐deficient freshwater fish governance. We highlight where change is needed to better embed justice, holism, and coordination in freshwater fish science and governance. Through hui and knowledge co‐production processes grounded in Te Ao Māori, we articulate six values that guide how research is designed and enacted. Sustaining freshwater fish and fisheries will require more than just more science or better science—it demands transforming the way knowledge is produced, shared, and applied to enable governance that honours Te Tiriti o Waitangi (the Treaty of Waitangi) and reflects the deep interconnections between ecological and cultural wellbeing.

In Vitro Antibacterial Activity of Glutathione Against Aeromonas veronii and Its In Vivo Effects on Intestinal Microbiota in Koi Carp ( Cyprinus carpio Var. koi ) - Haoyue Zhang; Jingfeng Sun; Zhuoran Han; Anli Wang (New Zealand Journal of Marine and Freshwater Research, 2026)
Aeromonas veronii is a pathogenic bacterium that threatens freshwater fish, including koi carp. Antibiotics used to control bacterial infections can disrupt the intestinal microbiota and promote antibiotic resistance. This study aimed to evaluate the in vitro antimicrobial activity of glutathione (GSH) against A. veronii and its impact on the intestinal microbiota of koi carp. To this end, we examined bacterial growth, biofilm formation, and motility of A. veronii . We further analyzed the intestinal microbiota composition by 16S rRNA high‐throughput sequencing and assessed disease resistance in koi carp after 7 days of dietary GSH supplementation. The results showed that GSH inhibited A. veronii growth, biofilm formation, and motility, with stronger effects at higher doses. GSH supplementation also significantly altered the intestinal microbiota, reducing potential pathogenic bacteria like Aeromonas and promoting beneficial ones. Moreover, GSH enhanced disease resistance, with treated fish showing lower cumulative mortality compared to controls. However, the GSH doses of 720 mg/kg caused hepatic burden, emphasizing the need for careful dose optimization. These findings highlight the significance of GSH in modulating the intestinal microbiota of fish, a process that may contribute to enhanced disease resistance, and emphasize the importance of optimizing its dosage for safe application in aquaculture.

Diversity and Potential Endemism of New Zealand Freshwater Rotifers Revealed Using Mitochondrial DNA Barcodes - Gemma E. Collins; Ian D. Hogg; Jonathan C. Banks; Clare R. Beet; Matthew A. Knox; Stacey J. Meyer; Steve M. Woods; Ian C. Duggan (New Zealand Journal of Marine and Freshwater Research, 2026)
Rotifers perform key functions in aquatic food webs and respond to environmental changes, thus providing sensitive indicators of water quality. However, rotifers are small, highly diverse, and difficult to identify for those lacking expertise. Monogononta are the largest taxonomic class of rotifers with over 1500 species described globally, and around 355 known from New Zealand; only four of these are currently recognised as endemics. Here, we morphologically identified 239 specimens (41 species) of New Zealand monogonont rotifers and obtained cytochrome c oxidase subunit 1 (COI) sequences to assess species‐level diversity. We found up to 20% sequence divergence and multiple genetic lineages within species. Using Barcode Index Numbers (BINs) and generalised mixed Yule coalescence (GMYC), we estimated 71–81 distinct genetic lineages, respectively, among the 41 species we sequenced. Only five lineages matched existing Barcode of Life Datasystems (BOLD) records, and 94% of BINs are thus far known only from New Zealand. Pending a more comprehensive global database, we conclude that many New Zealand lineages are likely to be endemic. Our curated sequences contribute to global repositories and provide a reference for future research and monitoring, particularly environmental DNA (eDNA) approaches.

Metabolic Dynamics of Central Carbon Pathways in Green‐Lipped Mussels under Heat Stress and Subsequent Recovery - Leonie Venter; Andrea C. Alfaro; Jeremie Zander Lindeque; Peet J. Jansen van Rensburg; Norman L. C. Ragg; Jessica A. Ericson; Natalí J. Delorme (New Zealand Journal of Marine and Freshwater Research, 2026)
Green‐lipped mussel ( Perna canaliculus ) aquaculture is vulnerable to environmental changes, which are increasingly being studied to pinpoint physiological, economic and ecological threats. This study utilised a targeted liquid chromatography‐mass spectrometry metabolomics approach, focusing on the central carbon metabolism, to examine the metabolic response of P. canaliculus haemolymph to heat stress (30°C) and multi‐point recovery (up to 47 h). Heat stress disturbed sugar‐based‐, amino acid‐ and purine‐derived metabolites, implementing anaerobic pathways and phosphagen breakdown, following initial thermal exposure, to support energy production. Time course recovery revealed varying metabolic adjustments in P. canaliculus , resulting in new metabolic setpoints in the heat‐stressed mussel group, which overlapped with the responses of the control group. Metabolic recovery in metabolites, such as pyruvate and malate, suggests the gradual return to aerobic energy generation, while amino acids, such citrulline, methionine and tyrosine, supported protein regulation and nitrogen homeostasis. In addition, purine‐derived metabolites (guanosine diphosphate, guanosine and guanine) linked to guanine‐based nucleotides support the use thereof towards energy production in heat‐stressed mussels, after which their levels stabilised, to control levels. Overall, the results show that P. canaliculus implements specific metabolic adjustments, as shifts in energy‐related and stress‐associated metabolites, to cope with short‐term high‐temperature exposure. After around two days of recovery at ambient temperatures, these metabolites do not simply return to baseline but instead stabilise at a new metabolic setpoint, suggesting a reprogramming of physiological homeostasis. These changes reflect an adaptive response in mussels that provides valuable insight for climate change adaptation and breeding resilient stocks.

Climate Change Projections for the Southwest Pacific Ocean Using Coupled Model Intercomparison Project (CMIP) Phase 5 and 6 Models: Implications for Physics, Biogeochemistry, Ecosystems, and Fisheries - Graham J. Rickard; Cliff S. Law; Matthew H. Pinkerton (New Zealand Journal of Marine and Freshwater Research, 2026)
This article analyses future projections of ocean properties for a region of the south‐west Pacific Ocean encompassing the New Zealand Exclusive Economic Zone under different climate change emission scenarios. Projections are updated and expanded from previous assessments using a “best” ensemble comprising both CMIP5 and CMIP6 earth system models. The updated projections show improved physical representations compared to previous projections based on CMIP5 models only. Contrary to the CMIP5 models alone, the new ensemble shows novel and distinct signatures associated with ocean circulation changes in the Bounty Trough that are consistent with recent observations. Previous results are extended to show how the reduced emission scenario SSP126 dampens future trajectories relative to the high emissions scenarios RCP8.5/SSP585 but does not return the end‐of‐century ocean state to that of the “present‐day” period [1976:2005]. Furthermore, analysis of archived output from three marine ecosystem models indicates that the south‐west Pacific Ocean total consumer biomass will reduce in the future, with reductions of 25%–51% by end‐of‐century under RCP8.5/SSP585 forcing. Overall, this article provides increased confidence of a substantially modified state of the southwest Pacific Ocean—physical, biogeochemical, and ecological—by end‐of‐century compared to present day.

Balancing Harvest and Habitat: A Framework for the Sustainable Management of Diadromous Galaxiids - Ben R. J. Crichton; Michael J. H. Hickford; Angus R. McIntosh; David R. Schiel; Andrew S. Watson (New Zealand Journal of Marine and Freshwater Research, 2026)
Managing New Zealand's diadromous Galaxias species and the associated whitebait fishery presents a complex challenge due to species‐specific differences in life‐history strategies, habitat requirements, and population dynamics that underpin responses to anthropogenic and environmental pressures. Consequently, effective management must balance the distinct vulnerabilities and dependencies of each species to ensure long‐term sustainability. This complexity is evident in the fishery's differential impacts, where fishing primarily affects early life stages in kōkopu species but has broader consequences for īnanga populations. The long lifespan of kōkopu species buffers them against short‐term recruitment variation, whereas the annual life cycle of īnanga results in availability of recruits having a direct effect on adult population size. Although fishing closures support larval escapement, the overall benefit to galaxiid populations depends heavily on the quality of habitats that support post‐larval development and adult spawning. An effective management strategy should, therefore, combine targeted fishing regulations with the protection and restoration of high‐quality habitats at regional and national scales to allow sustainable recreational and cultural harvests. This dual approach is critical for sustaining īnanga populations by ensuring sufficient recruits reach adulthood, while also supporting kōkopu by maximising adult carrying capacities and overall population productivity.

Passive Acoustic Monitoring Reveals New Insights Into the Acoustic Occurrence and Foraging Activity of Hector's Dolphins in Porpoise Bay, New Zealand - Max Harvey; Stephen M. Dawson; William J. Rayment (New Zealand Journal of Marine and Freshwater Research, 2026)
To effectively mitigate disturbances from human activities on vulnerable dolphin populations, it is crucial to understand fine‐scale variation in habitat use. This study investigated the habitat utilisation of a small subpopulation of Hector's dolphins ( Cephalorhynchus hectori ) in Porpoise Bay, New Zealand. Passive acoustic monitoring was conducted from January to August 2020 using two T‐PODs deployed in the inner and middle of the bay. Generalised additive models were used to investigate the influence of time of day, tidal state, season, and site on Hector's dolphin acoustic occurrence (measured as detection‐positive minutes per hour) and foraging activity (measured as foraging click trains per hour) in the bay. Dolphin acoustic occurrence was greatest during daylight hours and around high tide, particularly in the sheltered inner bay. Foraging activity mirrored these patterns and, like acoustic occurrence, showed no significant seasonal difference. Peak foraging activity occurred in the inner bay during the morning and early afternoon, shifting toward the middle of the bay later in the day. These findings expand our understanding of the drivers of Hector's dolphin habitat use and provide new insights for managing stressors to the subpopulation that uses Porpoise Bay.

Partial Fish Meal Replacement Coupled With Protein Restriction Reduces Protein and Fish Meal Usage Without Compromising Shrimp ( Penaeus Vannamei ) Growth and Health - Roghayeh Dehghani; Ebrahim Sotoudeh; Hossein Ouraji; Noah Esmaeili (New Zealand Journal of Marine and Freshwater Research, 2026)
Protein restriction and fish meal (FM) replacement are crucial for the sustainability of aquaculture. The effects of protein restriction (1 day feeding with dietary 40% protein and followed by 2 days feeding with dietary 35% protein, and using this cycle for 56 days) and FM replacement with an alternative protein mixture (yellow mealworm, spirulina, and rice concentrate; 4:1:4.5 ratio) on growth, body composition, hemolymph parameters, digestive enzymes, serological enzymes, immune and antioxidant system, and relative genes expressions in whiteleg shrimp ( Penaeus vannamei ) (0.63 ± 0.04 g) were tested. The levels of 0%, 33%, and 66% FM replacement (Control includes 25.5% FM, 40% protein, and 9% lipid) with and without protein restriction were adjusted (six treatments and three replicates per group) for 56 days. Applying protein restriction and 33% FM replacement simultaneously without impairment of weight gain, feed efficiency, immune and antioxidant parameters, and serological enzymes was possible. However, 66% FM substitution is excessive and resulted in reduced growth, body protein, digestive enzymes, immune and antioxidant system parameters, and serological enzymes. In conclusion, applying protein restriction along with 33% FM replacement is recommended for whiteleg shrimp farming.

Understanding Population Sustainability and Safe Consumption Limits to Inform Cultural Harvest of Tuna Within Nelson Lakes National Park - Jennifer E. Skilton; Simon D. Stewart; Tim Harwood; Catriona Sinclair (New Zealand Journal of Marine and Freshwater Research, 2026)
Customary harvest plays a vital role in expressing Māori identity, maintaining relationships with place and whakapapa, and transmitting mātauranga across generations. However, re‐engaging with traditional practices can be constrained by ecological risks and regulatory frameworks, particularly in protected areas. This study presents an integrated ecological and toxicological assessment of the customary longfin tuna ( Anguilla dieffenbachii ) harvest by Ngāti Apa ki te Rā Tō at Rotoroa, Nelson Lakes National Park. A dual knowledge approach combining mātauranga Māori and biophysical science was used to evaluate sustainability and food safety. From 2022 to 2024, annual harvests were paired with tuna monitoring and biological sampling. Otolith analysis revealed a mature slow‐growing population, and production modelling indicated that harvest levels (∼2–3% of annual cohort biomass production) were within conservative ecological limits. Mercury concentrations in muscle tissue averaged 0.31 mg·kg −1 (wet weight), with estimated dietary exposure from a single meal approaching short‐term health guidelines. Mercury levels were inversely correlated with condition factor, suggesting that the selective harvest of healthier individuals may reduce contaminant risk. These findings demonstrate that tikanga‐aligned harvest, supported by scientific assessment, can enable safe, sustainable customary use within conservation settings and offer a transferable model for iwi‐led freshwater management.

Translocating Intact Assemblages to Degraded Sites to Accelerate Ecological Recovery - Orlando Lam‐Gordillo; Emily J. Douglas; Sarah F. Hailes; Andrew M. Lohrer (New Zealand Journal of Marine and Freshwater Research, 2026)
Estuarine ecosystems are threatened by anthropogenic pressures such as climate change, coastal development, and increased nutrient and sediment inputs. These pressures are deteriorating ecological health and threatening the functioning and services that estuarine ecosystems provide. Here, we conducted a pilot study to assess the initial recovery capacity of highly eutrophic intertidal estuarine sediments. We theorised that the translocation of intact assemblages (including bioturbating macrofauna) into degraded areas would oxygenate sediments and initiate short term responses as a proxy of recovery. Our pilot study revealed that in situ experimental translocation enhanced macrobenthic richness, abundance, and diversity relative to controls at the degraded site. Translocation also affected ecosystem functions, with translocated sediments emitting less CH 4 relative to controls. This study suggests the potential of translocation approaches to jumpstart recovery. Our results were limited to only 5‐day experimentation as we focused on early‐stage recovery processes in sediment only; thus next steps should test the efficacy of different translocation designs, including longer duration, and the feasibility of upscaling in order to maximise the net benefits of this nature‐based restoration approach.

Issue Information (New Zealand Journal of Marine and Freshwater Research, 2026)

Diet of the Burmeister's Porpoise ( Phocoena spinipinnis , Burmeister, 1865) on the Northern Coast of Argentina - M. Candela Macagno; Antonella D. Padula; Alan F. Rosenthal; Diego H. Rodríguez; Pablo Denuncio (New Zealand Journal of Marine and Freshwater Research, 2026)
The Burmeister's porpoise ( Phocoena spinipinnis ) is a small cetacean endemic to South America, yet its diet is poorly known along Argentina's northern coast. We analyzed stomach ( n = 18) and intestinal ( n = 2) contents of 18 stranded or bycaught individuals collected from 1996 to 2024 between San Bernardo and Necochea (36°42′–38°33′S), Buenos Aires, Argentina. From the nine individuals with contents, 12 prey species were identified: 10 teleosts, 1 squid, and 1 crustacean. The striped weakfish ( Cynoscion guatucupa ) was the most important prey based on the index of relative importance (IRI% = 52.7), followed by Brazilian codling ( Urophycis brasiliensis ) (IRI% = 30.9). While the striped weakfish showed the highest frequency of occurrence (FO% = 27.8) and numerical abundance (NA% = 28.9), the Brazilian codling contributed most to biomass (BI% = 50.8). Teleost lengths ranged from 6.3 to 54.6 cm (23.7 ± 11 cm). All identified prey are of commercial interest, and 75% fall within commercial sizes. These results indicate a diet focused on demersal and pelagic coastal prey and suggest potential resource competition with local fisheries and sympatric predators. This is the first diet study for Burmeister's porpoise in northern Argentina and provides critical baseline data for its conservation.

Behavior and Gut Health of the Sea Cucumber Apostichopus japonicus with Yellow Intestinal Disease - Zihe Zhao; Yingzhuo Sun; Xiang Li; Sihan Wang; Jun Ding; Chong Zhao (New Zealand Journal of Marine and Freshwater Research, 2026)
Unfavorable environments have a serious impact on sea cucumbers and even lead to diseases in aquaculture. Yellow intestinal disease has a serious effect on land‐based aquaculture of sea cucumbers. This study is to clarify the effect of yellow intestinal disease on the behavior and gut health of sea cucumbers. We observed that feeding behavior significantly decreased in the sea cucumbers with yellow intestinal disease and that their righting response time was significantly longer compared to healthy individuals. Further, this study found that the heads of diseased sea cucumbers swung violently, and they preferred to stick to the wall of the tank rather than the bottom. This is contrary to sea cucumbers with enteritis disease. Additionally, we found that there was no significant difference in the thickness of the intestinal muscular layer between sea cucumbers with and without yellow intestine disease. However, the height of intestinal folds decreased, while the width significantly increased in diseased sea cucumbers. Novelly, the present study found that yellow intestinal disease did not change intestinal pepsin activity and flora abundance, although it reduced the feeding behavior of sea cucumbers and changed intestinal morphology. Yellow intestine disease is also different from the imbalance of intestinal microbiota caused by enteritis disease in sea cucumbers. Therefore, yellow intestine disease is probably not an enteritis disease, but a manifestation of sea cucumbers in the face of unfavorable environments. We suggest aquafarmers not treat sea cucumbers with yellow intestinal disease using the method to treat enteritis disease.

Realized Heritability and Genetic Gain of Growth Traits in the Portuguese Oyster, Crassostrea angulata - Sang Van Vu; Thiyagarajan Vengatesen; Hoang Huy Nguyen; Gde Raka Angga Kartik; Sarifah Aini; Angkasa Putra; Ziqiang Han; Hien Van Doan; Cao Truong Giang; Hyun-Woo Kim; Arief Wujdi; In Van Vu; et al. (New Zealand Journal of Marine and Freshwater Research, 2026)
Selective breeding is a fundamental tool for improving growth performance in aquaculture species. This study evaluated the realized response to selection, heritability, and genetic gain for three economically important traits consisting of shell length, soft tissue weight, and whole weight in the commercial edible Portuguese oyster ( Crassostrea angulata ) across three consecutive selection generations (S4, S5, and S6) and their respective control lines (C4, C5, and C6). A family‐based breeding design was implemented, and growth traits were measured at five time points during the grow‐out period (120, 180, 210, 270, and 365 days). The results revealed consistent genetic improvement in all three traits, with whole weight exhibiting the highest realized heritabilities (0.35–0.90) and genetic gains (up to 11.13%). Shell length and soft tissue weight also showed moderate realized heritabilities (0.11–0.79), with substantial genetic gains achieved over successive generations (7.69%–19.22%). Comparisons between the selected and control lines confirmed the effectiveness of the selection protocol. At 120 days, the whole weight of the S4 and S5 lines exceeded their respective controls by 8.7% and 11.1%. Moreover, at subsequent time points (180, 210, 270, and 365 days), genetic gains in the selected lines were significantly greater than in the control lines, with all improvements surpassing 8.5%. These findings demonstrate the efficacy of family‐based selection in C. angulata and highlight the potential for further genetic improvement of the lines under selection.

Seagrass Gains: Faster Growth, Better Condition, Less Effort for Juvenile Snapper ( Chrysophrys auratus ) - Jessica L. Campbell; Christine Stewart; Mark A. Morrison (New Zealand Journal of Marine and Freshwater Research, 2026)
Seagrass habitats are widely recognised as key nursery areas for juvenile fish, yet their specific role in supporting growth and condition remains incompletely understood. This study investigates the diet, growth and condition of juvenile (0+) snapper ( Chrysophrys auratus ) across multiple habitats in the Hauraki Gulf and northeastern New Zealand, with a focus on seagrass meadows. A total of 416 snapper were analysed for condition and growth, while diet composition was assessed from 425 gut samples. Results indicate that snapper within seagrass habitats exhibited significantly higher condition and faster growth rates than those in other habitats. However, contrary to expectations, gut fullness was lower in seagrass beds than in non‐seagrass habitats, despite higher prey availability in seagrass meadows. While diet varied among habitat types, no significant differences were detected between seagrass and non‐seagrass habitats. These findings suggest that the advantages conferred by seagrass are not directly linked to food intake but may result from reduced energetic costs associated with shelter from currents, improved foraging efficiency, or lower predation stress. The study highlights the vital role of seagrass meadows in supporting juvenile snapper populations and emphasises the need for conservation and restoration, particularly in areas where these habitats have been lost.

Gonadal Stage Identification and Oocyte Size Measurement Using DL Integrated Ultrasonography in Asian Sea Bass Lates calcarifer (Bloch, 1790) - Thakkarajan Senthil Murugan; Dani Thomas; Aritra Bera; Marappan Makesh; R. Annie Uthra; J. Preetha Roselyn; Samiappan Dhanalakshmi; Saad Yunus Sait; Sani Meenakshi; Selvam Thamizhazhagan; Govindarajan Thiagarajan; Muniyandi Kailasam; et al. (New Zealand Journal of Marine and Freshwater Research, 2026)
This study investigated gonadal stages in Asian sea bass ( Lates calcarifer ) using portable ultrasonography (Sonosite Edge II, 6–13 MHz), with histological validation of female (primary oocyte, early vitellogenic, ripe) and male (ripe) stages. Distinct echogenicity patterns differentiated sexes, and ultrasound‐based gonad measurements showed strong correlations with actual dimensions (ovary length R 2 = 0.9942, ovary width R 2 = 0.9886, testis length R 2 = 0.9857, testis width R 2 = 0.9793). Deep learning models achieved 99.9% accuracy for sexual maturity prediction (DenseNet‐161) and 99.8% for sex classification (VGG16). CNN regression with L1 and L2 regularization was used to predict oocyte diameters. The MAE (mean absolute error) was 6.31 µm for minimum and 5.20 µm for maximum oocyte diameter, which is less than 1.82% of the actual oocyte diameter (256–544 µm). These results, along with averaging over 10‐fold and small confidence intervals, indicate the robustness of the classification and regression methods. This raises the possibility of automating the classification of the fish reproductive stage by combining deep learning with ultrasound technologies and further developing contactless underwater ultrasonographic assessment of gonadal maturation in commercially important fin fish species. It also reduces the dependency on experts to infer sexual maturation details from ultrasound scans. The developed machine learning model is deployed in real‐time processor, Nvidia Orin, through which real‐time testing is carried out and the results are validated.

Forecasting Green‐Lipped Mussel Settlement via Feature Engineering and Random Forest Regressor - Emrah Hancer; Ivy Liu; Bing Xue; Ross Vennell; Mengjie Zhang (New Zealand Journal of Marine and Freshwater Research, 2026)
Spat settlement is vital in the life cycle of green‐lipped mussels ( Perna canaliculus ) and in the aquaculture industry, particularly in New Zealand. Spat, the juvenile stage of mussels, settle on substrates like ropes, initiating their growth into adults. The industry depends heavily on wild‐caught spat for farming, making successful settlement essential for maintaining a steady supply to meet production and market demands. Environmental factors, especially temperature, cause variability in spat availability. In this study, we propose a regression method based on temperature‐driven feature engineering to investigate the individual impact of mean weather temperature, temperature anomaly, and sea surface temperature on green‐lipped mussel spat settlement. The method first groups spat settlement locations using spatial clustering based on the DBSCAN algorithm. Next, preprocessing techniques are applied to clean and structure the data for analysis. Subsequently, feature engineering is performed to remove irrelevant and redundant features and create temperature‐driven lagged features. Finally, an Random Forrest regression model is built on the refined dataset. According to a series of experiments, models based on mean weather temperature and sea surface temperature show promising performance in forecasting spat settlement. In many locations, the model achieved an score between 0.6 and 0.8 for 1‐year forecasting.

An Urban Taonga: The Distribution and Abundance of Tuna in Urban Streams Across Tāmaki Makaurau, Aotearoa‐New Zealand - Nicole A. Whitelock; Kevin S. Simon; George L. W. Perry (New Zealand Journal of Marine and Freshwater Research, 2026)
Freshwater eels of the Anguilla genus are experiencing global decline, largely driven by human activity. In Aotearoa‐New Zealand, tuna (both shortfin and longfin eels) are similarly affected, with habitat fragmentation and modification key drivers of their decline. We investigated the distribution and abundance of tuna across regional, catchment and reach‐level scales in an urban environment. We developed species distribution models (SDMs) across the Tāmaki Makaurau (Auckland) region to explore patterns in tuna distribution across an urbanisation gradient. Additionally, we conducted a field survey across an urban catchment in Tāmaki Makaurau to assess the local habitat features associated with tuna presence and abundance. The predictive power of our SDMs was limited, and the field survey revealed that tuna were broadly distributed throughout the urban catchment, displaying only weak associations with specific habitat features. These findings suggest that in the absence of movement barriers, tuna can occupy a wide range of habitats throughout urban streams. However, the presence of tuna may not indicate suitable habitat for survival and growth, as their robust and opportunistic nature allows them to persist even in suboptimal environments.

Ingestion of Alexandrium pacificum Cysts by a Deposit Feeder: An Option for Ecosystem‐Based Approach Benefiting Aquaculture and Coastal Communities? - Leonardo N. Zamora; Kirsty F. Smith; Jacqui Stuart; D. Tim Harwood; Shenae L. Wales; Emillie M. F. Passfield; Lincoln Mackenzie (New Zealand Journal of Marine and Freshwater Research, 2026)
Harmful algal blooms caused by the paralytic shellfish toxin‐producing species Alexandrium pacificum have increased in recent years in one of the most important aquaculture regions of New Zealand, the Marlborough Sounds. Reoccurring blooms have created large cysts beds in the sediments throughout the sounds. In this region, large populations of the sea cucumber Australostichopus mollis can also be found. These deposit feeders potentially ingest the resting cysts of A. pacificum when feeding. To investigate this, we used molecular techniques to evaluate and quantify cyst ingestion, and chemical analysis to determine toxin accumulation in A. mollis . Results indicate that sea cucumbers can act as bioindicators of cyst distribution through their selective feeding behaviours, with high concentrations of A. pacificum DNA in foregut samples. Sea cucumbers could also serve as a biocontrol tool, as A. pacificum DNA concentrations decreased along the digestive tract, from the foregut to the hindgut, indicating a reduction in cyst number during the digestion process. Furthermore, no toxin accumulation was detected in the sea cucumber tissue. These encouraging results open the possibility for further research to evaluate the efficiency of integrated biocontrol management and the emergence of a multi‐impact aquaculture sector around this iconic New Zealand echinoderm.

Efficient Cadmium Removal Using Alginate‐Encapsulated Chlorella sp.: An Innovative Approach for Eco‐Friendly Aquatic Bioremediation - Nahla Bouzidi; Jamel Jebali; Tahar Gharred; Hatem Ben Ouada (New Zealand Journal of Marine and Freshwater Research, 2026)
Trace metals are frequently detected in aquatic ecosystems, raising serious concerns due to theirtoxicity to aquatic organisms and their potential transfer to humans through the food chain. Consequently, there is an increasing demand for eco‐friendly bioremediation strategies that preserve aquatic biota and environmental integrity, unlike conventional chemical or physical treatments. Microalgae, particularly Chlorella sp., have emerged as promising candidates for metal removal, especially when immobilized within biocompatible matrices. This study evaluated the cadmium (Cd 2+ ) binding capacity of Chlorella sp. and investigated the kinetics of cadmium retention using alginate‐immobilized cells. For the first time, potentiometric sensors incorporating alginate‐immobilized Chlorella sp. were developed and applied for cadmium detection. The system exhibited a reproducible near‐Nernstian response to Cd 2+ , with a slope of 29 mV per decade and a linear detection range from 10 −3, 42 to 10 −1, 67 M. The maximum cadmium fixation rate reached 205 μM Cd g −1 Chlorella sp. min −1 , with complete saturation achieved within 35–40 min. Cadmium retention involved coupled physicochemical interactions and biologically mediated processes, progressing through four successive stages: rapid surface binding, partial metal release, a transient adjustment phase, and establishment of a stable dynamic equilibrium. These findings highlight alginate‐immobilized Chlorella sp. as a sustainable efficient tool for cadmium bioremediation.

Mitogenomes of Seven Malaysian Marine Gastropods Recovered Using Genome Skimming - Nur Ilham Syahadah Mohd Yusoff; Han Ming Gan; Min Pau Tan (New Zealand Journal of Marine and Freshwater Research, 2026)
Gastropods (Phylum: Mollusca, Class: Gastropoda) are the most diverse group of molluscs, comprising about 80% of classified species. Despite this, mitochondrial genome (mitogenome) data for Malaysian marine gastropods remain scarce. In this study, we analyzed the complete mitogenomes of seven Malaysian intertidal gastropods from three subclasses: Caenogastropoda ( Chicoreus brunneus , Indothais malayensis ), Neritimorpha ( Nerita undata ), and Vetigastropoda ( Astralium calcar , Lunella cinerea , Trochus radiatus , Turbo chrysostomus ). These mitogenomes, rich in A + T content (60.9%–69.4%), ranged from 15,586 to 17,661 base pairs. Comparative analysis revealed that Vetigastropoda possessed longer protein‐coding genes, rRNAs, and intergenic regions but fewer overlapping genes. The gene order in Neritimorpha and Vetigastropoda mostly aligned with the ancestral gastropod mitogenome, whereas Caenogastropoda showed notable reorganization. Vetigastropoda species exhibited tRNA gene duplications, such as additional trnG and trnE . Most tRNAs had typical cloverleaf secondary structures, except trnS, which lacked a dihydrouracil arm. Phylogenetic analysis placed each species within its respective subclass and suggested a close evolutionary relationship between Neritimorpha and Vetigastropoda. This study provides new mitogenomic data essential for understanding the evolutionary biology, systematics, and biodiversity of Malaysian marine gastropods.

Issue Information (Reviews in Aquaculture, 2026)

The Fragmented Landscape of Shrimp Life Cycle Assessments: Uncovering Methodological Dependence and Analytical Blind Spots - Alena Calvo; Patrik J. G. Henriksson; E. J. Milner‐Gulland; Henry Travers; Joseph Poore (Reviews in Aquaculture, 2026)
Life cycle assessment (LCA) of shrimp aquaculture is hampered by widely divergent results, with reported impacts varying by more than fiftyfold across key categories. This systematic review of 16 peer‐reviewed LCAs provides quantitative evidence that much of this divergence is driven by analytical choices rather than on‐farm performance: In this case study covering 37 farming cycles, methodological differences in shrimp LCAs induced larger changes in global warming estimates for identical farm data compared to different farming practices. This issue is compounded by a lack of transparency, with only five of the 16 studies providing sufficient data for full reproducibility. We find that this methodological dominance is amplified by analytical blind spots, as most studies neglect critical environmental pressures such as land use change, biodiversity loss, and antibiotic use. To build a robust and comparable evidence base, we recommend representative studies, specific methodological harmonisation, mandatory inclusion of neglected impact categories, and improved reporting transparency. These improvements are essential for LCA to accurately guide the sector towards more sustainability.

Viral Disease Histopathology in Aquaculture Finfish: Organ‐Specific Pathological Changes and Diagnostic Insights, Referencing the World Organisation for Animal Health: A Review - Ram Babu Kurapati; Grace Ramena; Humphrey Wanjala; Sharon Gudapati; Yathish Ramena (Reviews in Aquaculture, 2026)
The aquaculture industry faces significant challenges from viral diseases, many of which are listed by the World Organisation for Animal Health (WOAH) as priority pathogens due to their impact on global finfish health and production. This review synthesizes current knowledge on the histopathology of key WOAH‐listed viral pathogens, including Koi Herpesvirus (KHV), Infectious Salmon Anaemia Virus (ISAV), Viral Hemorrhagic Septicemia Virus (VHSV), Megalocytivirus, Infectious Hematopoietic Necrosis Virus (IHNV), Spring Viremia of Carp Virus (SVCV), Salmonid Alphavirus (SAV), Tilapia Lake Virus (TiLV), and Epizootic Hematopoietic Necrosis Virus (EHNV). We provide a detailed examination of organ‐specific lesions, emphasizing spleen, kidney, gill, and gut pathology across diverse host species. Despite an expanding literature, important gaps persist, including inconsistent lesion scoring methods, limited comparative histopathological analysis across species, and underutilization of integrated molecular and histological diagnostics. Addressing these gaps through harmonized scoring systems and integrative diagnostic approaches is critical for improving disease diagnosis, control strategies, and sustaining aquaculture productivity worldwide. This review serves as a comprehensive resource to inform future research and health management practices related to viral diseases in aquaculture finfish.

Molecular and Endocrine Regulation of Ovarian Maturation in the Black Tiger Prawn ( Penaeus monodon ) and Associated Challenges in Its Aquaculture - Gourab Chowdhury; Josephine Nocillado; Abigail Elizur; Scott F. Cummins; Tomer Ventura (Reviews in Aquaculture, 2026)
Over the past four decades, substantial research has investigated the regulation of ovarian maturation and spawning in the black tiger prawn ( Penaeus monodon ). In this species, female reproduction is strongly suppressed by gonad‐inhibiting hormone (GIH) released from the eyestalk, making eyestalk ablation (ESA) the most widely adopted spawning‐induction strategy in aquaculture. Despite its effectiveness, the endogenous mechanisms that naturally overcome GIH‐mediated inhibition remain poorly understood, and only a limited number of stimulatory factors have been identified. As a result, the neuroendocrine and molecular regulation of reproduction throughout the ovarian maturation cycle remains incompletely resolved. Advancing this knowledge is essential for developing effective alternatives to ESA. This review synthesizes current advances in the neuroendocrinology of ovarian maturation in P. monodon , identifies key knowledge gaps, and summarizes molecular approaches evaluated as potential replacements for ESA. Collectively, this review supports ongoing efforts to develop sustainable and animal welfare‐friendly spawning‐induction strategies for P. monodon aquaculture.

Advances in Understanding Micro‐ and Nanoplastic Toxicity on Farmed Fish and Emerging Nutritional Interventions - Quansen Xie; Fang Chen; Xiaoping Huang; Jun Wang; Dizhi Xie (Reviews in Aquaculture, 2026)
Micro‐ and nanoplastics (MNPs), encompassing microplastics (MPs, diameters

Correction to “Global Warming Affects the Pathogenesis of Important Fish Diseases in European Aquaculture” (Reviews in Aquaculture, 2026)

Understanding the Relationship Between Rhizocephalans and Their Hosts From the Lens of Omics: Implications Towards Crustacean Aquaculture - Yang Yu; Youji Wang; Kianann Tan; Menghong Hu; Nor Afiqah‐Aleng; Melissa Beata Martin; Lihan Zhang; Hanafiah Fazhan; Khor Waiho (Reviews in Aquaculture, 2026)
The continuous development of high‐throughput sequencing technologies has revolutionised the field of food production and agriculture, including aquaculture. In addition to fish, crustaceans play a crucial role in supporting coastal economies and serve as a valuable source of high‐quality protein worldwide. Therefore, the prevention and treatment of diseases, especially in commercially valuable crustaceans, are of paramount importance. Among the various parasites affecting crustaceans, rhizocephalan parasites have recently gained widespread attention due to their severe effects on hosts, including moult inhibition, parasitic castration and feminisation, reduction in metabolism and survival, and behavioural changes. This review employs a systematic literature review approach to summarise progress in omics research regarding host‐rhizocephalan interactions. The final dataset comprised 12 articles from four rhizocephalan families (Thompsoniidae, Sacculinidae, Polyascidae, and Peltogasterellidae). The review further discusses advances in omics research across five main functional categories: growth and moulting, metabolism, sex differentiation and reproduction, immunity and disease, and population genetics and evolution. Differentially expressed genes, proteins, metabolites, and pathways identified in rhizocephalan‐related omics studies serve as a valuable molecular database to understand host responses and rhizocephalan infection strategies. Key factors, including juvenile hormone esterase ( JHE ), thioredoxin, Kazal‐type protease inhibitor ( KPI ), heat shock proteins ( HSP70/HSP90 ), and cathepsins , are multi‐functionally involved in host‐rhizocephalan interactions. However, knowledge gaps persist, hindered by limitations in diagnostic tools and data integration. Future directions, such as single‐cell sequencing (scRNA‐seq), multi‐omics approaches, and protein–protein interaction (PPI) networks, offer promise for advancing our understanding of host–parasite dynamics, providing insights for rhizocephalan parasitology control in sustainable crustacean aquaculture health.

Transcriptome RNA Sequencing Analysis Provides Novel Insights Into Reproduction and Gonadal Development in Grouper Fish - Silvana Rahayu; Kwaku Amoah; Yu Huang; Jia Cai; Melati Sukma; Huapu Chen; Mouyan Jiang (Reviews in Aquaculture, 2026)
Grouper fish (family Serranidae) are a group of fish with high ecological and economic value in the global fishing industry and is generally protogynous (from female to male). Sexual reversal process is a complex biological mechanism that involves remodeling the gonad, requiring simultaneous coordination among various genes and molecular pathways. Transcriptome analysis has become an important approach to understanding the basic mechanisms of various biological processes. As contained in this paper, data were synthesized from the findings of RNA‐seq‐based transcriptomic studies that reveal key genes and pathways, such as foxl2 , Cyp19a1a , DMRT1 , Sox9 , AMH , and the HPG axis in gonadal differentiation and sexual transition in grouper fish. Although most of the data are descriptive and come from the bulk RNA‐seq approach, these findings provide consistent molecular insights into the mechanisms of reproductive regulation. One of the approaches that is now widely used is RNA‐seq‐based transcriptome analysis through NGS technology. This technology enables the development of reproductive biomarkers, detailed gene expression analysis, sex selection strategies, identification of critical molecular pathways, identification of key genes, as well as gene‐based approaches to support cultivation and conservation efficiency. This review emphasizes the role of RNA‐seq as a fundamental tool in building the scientific foundation for the study of grouper fish reproduction, with possible implications including more effective reproductive management, improved breeding techniques, the implementation of genetic therapies, increasing aquaculture productivity, and species conservation and recovery.

Environmental Enrichment in Aquaculture: Linking Welfare Goals to Practical Applications - Olivia Spiliopoulos; Sunil Kadri; Michelle Sinclair; Myriam Vanderzwalmen; Culum Brown (Reviews in Aquaculture, 2026)
Aquaculture is the fastest growing food production sector globally, comprising freshwater and marine species reared under highly variable farming contexts, ranging from extensive earthen ponds to intensive recirculating and sea‐based systems. Together with growth, production has also intensified, and the welfare of fish farmed in these systems has thus gained increased recognition as an essential contributor to sustainability of aquaculture. Environmental enrichment has emerged as a promising welfare management tool to improve fish welfare and deliver potential production benefits by promoting species‐appropriate behaviour and reducing chronic stress; however, its effective implementation remains highly context dependent. This review synthesises current knowledge on environmental enrichment across five categories: Physical, Sensory, Dietary, Occupational, and Social, to evaluate their potential to produce measurable changes in physiological and behavioural indicators of welfare. Enrichment strategies are further assessed for their practicality and feasibility, identifying areas where enrichment is already integrated into aquaculture and where further innovation is required. To guide implementation, a goal‐oriented framework is proposed that outlines a stepwise process for aligning welfare objectives with appropriate enrichment strategies while considering species, system, and operational contexts. This combined approach reframes environmental enrichment from a peripheral addition to an integrated component of welfare management in aquaculture.

Antimicrobial Resistance in Salmonella Across Aquaculture, Seafood and Related Aquatic Environments: A Scoping Review With Exploratory Textual Analysis - Cristiane Coimbra de Paula; Yuri Duarte Porto; Vinícius Silva Castro; Érica do Carmo Dias Matos; Adelino Cunha‐Neto; Ricardo César Tavares Carvalho; Luciana Kimie Savay‐da‐Silva; Eduardo Eustáquio de Souza Figueiredo; Tathiana Ferguson Motheo (Reviews in Aquaculture, 2026)
Salmonella spp. are major foodborne pathogens linked to high morbidity and mortality, and their increasing antimicrobial resistance represents a growing global public health threat. This scoping review followed the PRISMA protocol and included 93 original articles on the microbiological diagnosis and antimicrobial resistance profiles of Salmonella spp. isolated from aquaculture, seafood and related aquatic environments. Studies were retrieved from PubMed, Scopus, SciELO, ScienceDirect, and Web of Science, covering 2004 to 2024. Eligible studies included samples from aquaculture systems, fisheries, seafood products, or related environmental and food‐processing sources. Extracted data addressed country of origin, resistance profiles, resistance genes and phenotypes, and multidrug‐resistant (MDR) serovars. Abstracts were analyzed using classical lexical statistics, word clouds, similarity graphs, and hierarchical descending classification in R and Iramuteq. Among studies, 42.8% originated from Asia, with the highest publication count in 2021. Textual analysis showed strong associations among the terms “ Salmonella ”, “isolates”, “resistance”, and “antimicrobials”. Hierarchical classification revealed themes such as “surveillance”, “pathogens in food”, and “One Health”. Tetracycline exhibited the highest resistance rate (83.3%) across studies, and the disk diffusion method was the most frequently used (72%). Commonly reported resistance genes included qnrS (fluoroquinolones), blaTEM‐1 (β‐lactamases), sul3 (sulfonamides), and dfrA12 (trimethoprim). Virulence genes such as invA, fimA , spvC , and stn were also identified. The most frequently reported MDR serovars were S. Typhimurium and S . Newport. This review highlights the relevance of antimicrobial‐resistant Salmonella in aquaculture and reinforces the need for robust monitoring aligned with One Health strategies to ensure safe and sustainable production.

Bridging Aquaculture and Human Medicine: A Comprehensive Review of Zebrafish Models for Chronic Kidney Disease - Feng‐Yi Guo; Hao‐Yu Yang; Lan‐Chen Zhang; Xiang‐Ru Liu; Pan‐Pan Jia; De‐Sheng Pei (Reviews in Aquaculture, 2026)
Chronic kidney disease (CKD) poses a significant global health burden, necessitating robust animal models for mechanistic studies and drug discovery. Zebrafish offers unique advantages as a powerful models in kidney disease, including high‐throughput compatibility, optical transparency, and significant genetic and nephron homology with both humans and farmed teleosts. However, challenges, such as the species' potent regenerative capacity and a lack of standardized diagnostic thresholds, hinder their broad application. This review systematically summarizes four principal induction strategies: environmental stress, nephrotoxic chemical exposure, CRISPR/Cas‐based gene editing, and transgenesis. We further outline a validation pipeline that integrates functional assays, morphometrics, and histopathology, while advocating for cross‐laboratory harmonization. Additionally, we compare risk factors for CKD and CKD of unknown etiology (CKDu), emphasizing environmental contributors. Collectively, we propose zebrafish as a reproducible platform for aquaculture applications, specifically for nephropathy early‐warning systems and functional feed assessment, and for human therapeutic research. These standardized models hold great promise for high‐throughput drug screening and elucidating disease mechanisms, facilitating the translation of findings to both aquaculture and clinical medicine.

A Review of Advances in Nutrition Research towards Commercial Aquaculture of Pompanos, Trachinotus spp. - Nicholas Romano; Juan F. Paredes; Fernando Yamamoto; Paul S. Wills; Charles R. Weirich; Kenneth L. Riley (Reviews in Aquaculture, 2026)
Among the jack family (Carangidae), pompanos, Trachinotus spp., are the most farmed globally. The top four most aquacultured species are golden pompano, T. ovatus , snubnose pompano, T. blochii , Indian pompano, T. mookalee , and Florida pompano, T. carolinus . While initial efforts to culture these species heavily relied on wild‐caught small fish of various species (commonly referred to as ‘trash fish’) for growout, pompanos can readily accept and thrive on formulated pelleted feeds. This has largely been accomplished through decades of nutritional research where marine‐based ingredients can be feasibly replaced with plant and animal‐based protein mixtures as long as essential amino acids, including taurine, and long‐chain polyunsaturated fatty acids meet their nutritional requirements. Obstacles still exist, including relatively poor feed efficiency, despite having a high digestibility of various ingredients, along with major research gaps in pompano nutrition and feed management of late juveniles to near‐market sized adults. Additionally, nutritional research on vitamin requirements as well as “functional feeds” and “finishing diets” designed for pompano is also relatively limited. After briefly describing the research history and production of the four most commonly farmed Trachinotus species, the main focus will be on discussing the feasibility of using alternatives to marine‐based ingredients, the influence of different starch sources, vitamin/mineral requirements, the success of “functional feeds” and the effectiveness of different feed management strategies in pompano aquaculture.

Evaluation of Non‐Conventional Plant‐Based Feed Ingredients ( NPFIs ) for a Sustainable Aquafeed Industry - Baki Aydın; Orhan Tufan Eroldoğan; Ebru Yilmaz; Md. Tawheed Hasan; Thavasimuthu Citarasu; Süleyman Akhan; Sebahattin Ergün; Lee Seong Wei; Zulhisyam Abdul Kari; Yasuhito Shimada; Takuro Shinkai; Hany M. R. Abdel‐Latif; et al. (Reviews in Aquaculture, 2026)
The development of aquafeed is indeed crucial for maintaining sustainability in aquaculture. Conventional plant‐based protein meals, such as soybean meal, canola meal, DDGS, cottonseed, corn meal, and their combinations have been extensively explored in aquafeed used in fed‐aquaculture systems. Nevertheless, endeavors and scholarly interest in incorporating non‐conventional plant‐based feed ingredients (NPFIs) with nutritional value into aquafeeds for sustainable aquaculture production remain ongoing. NPFIs that have yet to be fully explored and authorized might be considered as a novel source of protein, lipids, carbohydrates, and functional biomolecules. There are a diverse number of NPFIs, such as seed meal, leaf meal, seed cake, kernel meal, by‐product meal, and fruit waste meal that exhibit considerable diversity in their nutritional profile, with the crude protein content varying from 2.4% to 76.4% and crude lipid levels ranging from 0.2% to 39.5%. Besides, the presence of various amounts of fatty acids, amino acids, and phytochemicals may positively enhance growth and feed efficiency and promote the overall health of aquatic species, making them considered as valuable aquafeed ingredients. This review, therefore, aims to comprehensively investigate and critically evaluate the utilization of NPFIs as novel feed ingredients for the growth, health, and welfare of farmed aquatic species. A Strengths‐Weaknesses‐Opportunities‐and‐Threats (SWOT) analysis has also been conducted to assess the feasibility of NPFIs for aquafeeds. As a result, this review indicates that the integration of NPFIs into aquafeeds as feedstuffs or feed additives offers great potential in the sustainable development of aquaculture production for all parties involved, particularly small‐scale producers.

The Protozoan Parasite Perkinsus marinus in Bivalve Mollusks From Mexico: A Review - Jorge Cáceres‐Martínez; Naoki Abraham Kawamoto‐Camacho; Rebeca Vásquez‐Yeomans; Roberto Cruz‐Flores (Reviews in Aquaculture, 2026)
Unusual mortalities of the Eastern oyster Crassostrea virginica were reported in 1946 along bays of the Mississippi River, USA, and later attributed to the protozoan Perkinsus marinus . Initially described as Dermocystidium marinum , the parasite was reclassified and has since become one of the most extensively studied pathogens of bivalve mollusks. It is listed by the World Organization for Animal Health (WOAH) because of its significant impact. In Mexico, the parasite was first detected in C. virginica from Gulf of Mexico coastal lagoons during the 1950s. Despite decades of research, no international‐scale review of Mexican studies has been conducted. Twenty‐five articles and eight postgraduate theses were identified that have investigated P. marinus and presumptive P. marinus in Mexico. One of the most significant findings is its detection on the Pacific coast, linked to oyster translocations. The parasite has been reported in a wide diversity of bivalve mollusks belonging to the families Mytilidae, Ostreidae, Pinnidae, Veneridae, and possibly Arcidae. Only two field studies have associated the parasite with mortalities, and their results remain inconclusive. Current evidence suggests that strain variability, host susceptibility, and environmental conditions of Mexico may reduce the lethality of P. marinus . Further research is needed to clarify parasite virulence, host–parasite interactions, and environmental influences. Such studies would not only improve risk assessment in Mexico but also alert other regions to the potential biosecurity significance of P. marinus in diverse bivalves. In addition, Perkinsus chesapeaki and Perkinsus spp. have also been tentatively detected by molecular genetic analyses, which deserve research.

Existing Soundscapes and the Impact of Noise on the Welfare of Farmed Salmonids: A Review - Kathy Overton; Tim Dempster; Marco A. Vindas; Frode Oppedal; Luke T. Barrett (Reviews in Aquaculture, 2026)
Understanding how farmed salmonids sense and respond to their environment is key to securing animal welfare and efficient production. However, hearing has rarely received attention, despite the omnipresence of underwater sound and its potential effects. We describe how and what salmonids hear, and explore how hearing may differ between wild and farmed conspecifics. We then conduct two systematic reviews, to: (1) understand the existing soundscapes experienced by farmed salmonids; and (2) identify potential short‐ and long‐term impacts of sound on salmonid behaviour and physiology. Sound can be measured via pressure changes or particle motion; pressure levels are commonly reported, whilst particle motion is rarely measured due to logistical challenges. Salmonids have an open, physostomous swim bladder, relying primarily on their lateral line to sense sound via particle motion. Because of this, they are most sensitive to low frequencies, with startle responses most apparent between 7 and 400 Hz. Few studies have tested for effects of sound on salmonid physiology, although there is evidence that some sound exposure regimes lead to chronic stress, whilst very loud sounds (e.g., cumulative sound exposure level > 216 dB re 1 μPa 2 a) can cause fatal injuries. Quantifying salmonid aquaculture soundscapes, their potential welfare impacts, and strategies to mitigate these impacts should form a new frontier in salmonid aquaculture research. We make a series of recommendations, specifically: (1) conduct targeted research to fill knowledge gaps; (2) develop a standardised protocol to measure and report sound in salmonid aquaculture; and (3) apply mitigation strategies to reduce impacts of noise.

Aquaculture in Maritime Spatial Planning Frameworks and Its Contribution to Global Food Security - Øivind Strand; Hui Liu; Joao G. Ferreira; Ramon Filgueira; Ellen Sofie Grefsrud; Pia Kupka Hansen; Qianwen Sun; Jenny Weitzman (Reviews in Aquaculture, 2026)
Increase in aquaculture toward realizing the potential of the ocean as a key food provider requires comprehensive and proactive management approaches to mitigate impacts on coastal areas and to secure space for sustainable aquaculture development in both inshore and offshore areas. Maritime Spatial Planning (MSP) and Marine Functional Zoning (MFZ) are policy instruments employed in the management and regulation of multiple human activities to balance social, economic, and environmental objectives. This work reviews the processes and stages of aquaculture integration into these marine spatial planning frameworks (MSP and MFZ) in major producers, China, the EU, Norway, and Canada. Implementation of aquaculture in the spatial planning frameworks varies widely, partly because the nations reviewed are at different stages of aquaculture development, and partly due to the heterogeneity of institutions, traditions, social acceptance, marine space, and governance. The common challenge of aquaculture impacts and interactions with the environment contribute to the complexity of regulating space for mariculture development. The apparent weak and in some cases receding position of aquaculture in the maritime spatial planning frameworks reviewed here warrants considerable concern with respect to expectations of marine aquaculture as a route for ensuring future seafood provision. There is a need to strengthen the position of aquaculture in marine spatial planning frameworks, particularly when considering its expansion in areas with potential for development. It is recommended that the global scientific, management, and regulatory communities work together with local actors to develop and provide accessible tools that will address sustainability challenges ahead.

Heat Shock Proteins in Aquatic Larvae: Nutritional and Live Feed Modulation of Chaperone‐Mediated Stress Physiology in Fish and Shellfish - Yathish Ramena; Ram babu Kurapati; Thomas Bosteels; Grace Ramena (Reviews in Aquaculture, 2026)
Heat shock proteins (HSPs) are highly conserved molecular chaperones that maintain proteostasis under environmental and physiological stress. In aquaculture research, HSP responses have been studied primarily in relation to temperature, salinity, pollutants, and pathogens in juvenile and adult stages, whereas the nutritional regulation of HSP dynamics during early larval development remains poorly resolved. This review synthesizes current knowledge on the functions and regulation of major HSP families (HSP100, HSP90, HSP70, HSP60, and small HSPs) in fish and shellfish larvae and develops mechanistic frameworks linking live feed characteristics to HSP‐mediated stress physiology. Drawing on evidence from Artemia and other crustacean and fish models, we propose a Live Feed–Proteotoxic Stress–HSP (LFP–HSP) axis that integrates feed digestibility, metabolic and oxidative load, and feed‐associated microbiota as key drivers of HSP induction and innate immune function. We further describe ROS–HSP–innate immunity crosstalk and introduce the concept of HSP‐conditioned resilience, whereby controlled, diet‐mediated HSP induction enhances larval tolerance to subsequent husbandry stressors and pathogen challenge. Comparative analysis of commonly used live feeds, including Artemia, rotifers, Moina, Daphnia, and copepods, indicates that differences in nutrient composition, structural complexity, and microbial associations generate distinct HSP expression profiles and stress phenotypes in consuming larvae. Finally, we discuss the application of HSP‐based biomarkers for live feed evaluation, larval quality assessment, and the development of feeding strategies that minimize chronic cellular stress while maximizing robustness in hatchery production of fish and shrimp.

Correction to “Mechanisms of Fish Intestinal Damage Under Environmental Stress: Insights From Carbonate Saline–Alkali Water Perspective” (Reviews in Aquaculture, 2026)

Monoterpenes: Functional Additives for Reducing Antibiotics in Aquaculture - Danilo Vitor Vilhena Batista; Barbara Silveira Souza; Caio Francisco Santana Farias; Ana Paula de Souza; Alexandre Vaz da Silva; Emilly Monteiro Lopes; Elenice Martins Brasil; Maurício Laterça Martins; José Luiz Pedreira Mouriño; Marco Shizuo Owatari (Reviews in Aquaculture, 2026)
Aquaculture is a rapidly growing industry that supplies fish for global consumption. However, the intensive production practices have resulted in disease outbreaks, largely driven by the misuse of antibiotics. Natural alternatives, such as monoterpenes, which are biocompounds derived from essential oils obtained from plants like thyme and oregano, are being investigated for their antimicrobial properties. Research has shown that monoterpenes can effectively reduce mortality rates in aquaculture, providing a sustainable solution for disease management without the negative environmental impacts associated with antibiotics. This approach has the potential to promote healthier and more environmentally friendly fish production. Monoterpenes have demonstrated promising results in enhancing fish resistance to pathogens, which could potentially reduce the reliance on antibiotics in aquaculture. However, the economic feasibility of incorporating these compounds into fish diets has not been thoroughly examined, which may hinder their widespread adoption. Clear economic data is essential to evaluate the costs and benefits of using monoterpenes in aquaculture, as uncertainties regarding financial returns could discourage producers and investors. Without this information, the market acceptance of aquafeeds containing monoterpenes may be limited, affecting the progress of cleaner and more sustainable fish farming practices. This review aims to address the gaps in knowledge regarding the widespread use of phytobiotics, specifically focusing on monoterpenes and their impact on the aquaculture industry. It will delve into their mechanisms of action, effectiveness in protecting aquatic animals, and recent developments in combating bacterial infections, while also discussing the risks posed by antimicrobial resistance.

Toxicological Insights Into Multiple Pesticide Exposures in Red Swamp Crayfish ( Procambarus clarkii ): Molecular Mechanisms, Risk Assessments, and Future Perspectives for Aquaculture - Dan‐Dan Bian; Zi‐Yi Xing; Shuang‐Gui Dai; Xiang Lu; Dai‐Zhen Zhang; Bo‐Ping Tang; Bao‐Jian Zhu; Qiu‐Ning Liu (Reviews in Aquaculture, 2026)
The rice–crayfish integrated system (RCIS) is vital to Asian aquaculture, yet its sustainability is threatened by a critical paradox: pesticides used in rice cultivation jeopardize the health of the red swamp crayfish ( Procambarus clarkii ) and the safety of its products. This review systematically synthesizes evidence establishing oxidative stress as the central hub linking pesticide exposure to multilevel toxicity in P. clarkii . We delineate how pesticides dysregulate key pathways (PI3K/AKT/mTOR, MAPK, NF‐κB), triggering apoptosis, metabolic disruption, and immunosuppression. A pivotal mechanism involves pesticide‐induced gut microbiota dysbiosis, which diminishes beneficial short‐chain fatty acids and enriches pathogens, thereby amplifying intestinal barrier damage and host vulnerability. These interconnected processes collectively stunt growth and heighten susceptibility to pathogens like white spot syndrome virus (WSSV). Beyond organismal effects, we evaluate environmental pesticide fate and propose a novel risk assessment framework integrating these sublethal endpoints. Our proposed mitigation strategies include eco‐friendly pesticides, ecological engineering, and microbiome‐directed interventions. We advocate for future research prioritizing multi‐omics and mixture toxicity assessment. By deciphering this toxicity cascade and translating insights into practice, this review aims to protect the productivity, ecological integrity, and food safety of integrated aquaculture systems for long‐term sustainability.

Macro‐Hybrid and Micro‐Hybrid of Fish - Qizhi Liu; Anmin Liao; Min Tao; Qinbo Qin; Kaikun Luo; Chun Zhang; Shi Wang; Yi Zhou; Fangzhou Hu; Yude Wang; Chang Wu; Wuhui Li; et al. (Reviews in Aquaculture, 2026)
This study reviews the progress in fish breeding, focusing on distant hybridization and gynogenesis, and introduces the theory of macro‐hybrid and micro‐hybrid. The macro‐hybrid refers to the allo‐progeny derived from distant hybridization, including the allo‐progenies. The micro‐hybrid refers to the auto‐progenies derived from distant hybridization or heterologous sperm‐induced gynogenesis, which possess a genome derived predominantly from the maternal but contain DNA fragments originating from the paternal. Macro‐hybrids induce significant phenotypic changes, while micro‐hybrids improve growth rate and stress resistance. Both hybridization and gynogenesis exhibit high selective pressure. This review elucidates how selective pressures (homozygosity + heterologous sperm + cold/heat shock) of the heterologous sperm‐induced gynogenesis contribute to the generation of effective genetic variations. The study also presents the technologies of macro‐hybrid and micro‐hybrid. In macro‐hybrids of distant hybridization, parental chromosome numbers are closely matched, enabling the formation of fertile allo‐diploid and allo‐tetraploid strains. In micro‐hybrid of distant hybridization, equal or differing chromosome numbers between parents yield fertile auto‐tetraploid and auto‐diploid strains. In micro‐hybrid of heterologous sperm‐induced gynogenesis, equal or different chromosome numbers between parents yield auto‐diploid strains. The integration of heterologous sperm‐induced gynogenesis, back‐cross, and self‐cross strategies can address the issue of all‐female progeny resulting from gynogenesis. A series of auxiliary breeding techniques is established to support the macro‐hybrid and micro‐hybrid breeding. Case studies of superior fish strains developed through macro‐hybrid and micro‐hybrid breeding are presented. The establishment of macro‐hybrid and micro‐hybrid theory and breeding technologies holds significant value for fish breeding.

The Genus Aeromonas in Aquaculture: A Comprehensive Review of Prevalence, Virulence, and Antibiotic Resistance With an Emphasis on Key Pathogenic Species - Luo‐tao Tao; Dong‐peng Gao; Yi‐ling Liu; Wu‐wen Sun; Xiao‐feng Shan (Reviews in Aquaculture, 2026)
In the burgeoning global aquaculture sector, safeguarding water quality and mitigating the impact of aquatic pathogens are paramount to maximizing industry profitability and ensuring the safety of aquatic products. Among the myriad bacterial species impacting aquatic ecosystems, the genus Aeromonas emerges as a particularly influential player in both natural and aquaculture settings. This ubiquitous group of bacteria not only precipitates a range of diseases in aquatic organisms, compromising aquaculture productivity and product quality, but also harbors zoonotic potential, posing a threat to human health. Furthermore, the rampant use of antibiotics in aquaculture has precipitated a concerning trend of Aeromonas resistance to multiple classes of antimicrobial agents, exacerbating the challenges associated with disease prevention and control. This review endeavors to comprehensively explore the prevalence, virulence determinants, and the evolving landscape of antibiotic resistance in Aeromonas within the context of aquaculture. By synthesizing and critically appraising the extant literature on Aeromonas , we aim to provide a robust scientific basis for the management of aquatic diseases and antimicrobial resistance, offering strategic insights for the sustainable advancement of the aquaculture industry.

Stress Nutrition in Aquatic Animals: From Definition to Practice - Jian Zhang; Qianwen Ding; Ruobing Lou; Yuanpei Zhang; Yuanyuan Yao; Yalin Yang; Zhen Zhang; Chao Ran; Zhigang Zhou (Reviews in Aquaculture, 2026)
Aquaculture faces numerous challenges, with stress being one of the major issues that lead to growth loss, metabolic disorders, weakened immunity, redox imbalance, and organ damage in aquatic animals. Nutritional intervention is one of the effective strategies to address these problems. Traditional research has primarily focused on the impacts of a single stressor on specific aspects of particular aquatic animal species. However, in practical scenarios, aquatic animals are often simultaneously exposed to multiple, overlapping stressors. Thus, it becomes crucial to investigate the specific role of nutrients in anti‐stress and to consider their synergistic effects when used in combination. Nevertheless, some nutrients have overlapping functions or differences in the degree of treatment. Thus, it is necessary to synthesize the existing nutritional research on stress alleviation in order to provide more precise and economical nutritional strategies. This paper reviews the research progress in stress nutrition in aquatic animals, including the classification of stressors, stress response processes and their combined effects, as well as the development of nutritional strategies offering new perspectives for managing stress in aquaculture. It defines stress nutrition from the perspective of essential nutrients, conditional essential nutrients, and homeostasis regulation of gut microbiota, emphasizing the dynamic adjustment of nutritional requirements in response to various stressors. Additionally, it also provides an in‐depth discussion of the research progress, challenges, and future prospects in this field. Continued exploration in this field will reduce stress‐associated losses in aquaculture and promote the efficiency of food supply by this important agricultural sector.

Current and Future Approaches to Determining Amino Acid Requirements in Crustaceans - Adam Yeap; Chris G. Carter; Basseer Codabaccus; Quinn P. Fitzgibbon; Gregory G. Smith (Reviews in Aquaculture, 2026)
Nutrition is crucial in aquaculture, with feed ingredients and manufacturing being one of the largest expenditures. The effectiveness of a feed in promoting animal growth and health is dependent on ingredients with appropriate nutritional profiles. Proteins are a costly component of aquaculture feeds; moreover, dietary crude protein requirements for crustaceans can be high, sometimes exceeding 50% of the diet. As proteins are composed of amino acids, understanding species‐specific amino acid requirements is essential for developing cost‐effective, customised commercial feeds. Several methods have been used to determine crustacean amino acid requirements, each with advantages and limitations. Given the varied feeding behaviours between crustacean species, some methods may only be appropriate for certain species. In this review, we propose the Requirements by Ration Level approach as the most suitable method for developing factorial models for feed formulation. This method considers amino acid intake, retention, and loss, whilst integrating digestibility, growth, and chemical composition. It is reliable, accurate, and addresses concerns of amino acid balance changes previously raised in the literature. By using a broken convex curve model instead of a broken line model, more realistic predictions are produced, reflecting dynamic conditions and transitions towards the plateau where the amino acid requirement is met. Additionally, technological advancements have allowed complementary studies in omics, nutritional physiology, and true protein. This review highlights various methods for determining amino acid requirements and demonstrates how the Requirement by Ration Level approach can produce consistent results across experiments, reducing experimental repetition and advancing our understanding of amino acid requirements.

Cover Image - Qizhi Liu; Anmin Liao; Min Tao; Qinbo Qin; Kaikun Luo; Chun Zhang; Shi Wang; Yi Zhou; Fangzhou Hu; Yude Wang; Chang Wu; Wuhui Li; et al. (Reviews in Aquaculture, 2026)
The cover image is based on the article Macro‐Hybrid and Micro‐Hybrid of Fish by Shaojun Liu et al., https://doi.org/10.1111/raq.70106 . image

Impacts of Salmonid Fish Production on River Water Quality: A Critical Appraisal of the Evidence - Anna N. S. Michalopoulou; Nic R. Bury; Robert A. Holland; Imogen Speck; Tim Sykes; Gail Taylor; Marc G. Dumont; Kelvin S.‐H. Peh (Reviews in Aquaculture, 2026)
Rivers are recognised as providing valuable goods and services to society, and as hotspots of global biodiversity. Fish farming is an economically important activity associated with river systems; however, the effects of this industry on river health are not entirely understood. Studies evaluating interactions between freshwater fish farms and rivers are limited; therefore, we conducted a systematic review and an appraisal of evidence quality to assess the impacts of salmonid fish farming on river water quality. The review revealed that two main types of water quality indicators are generally applied: physicochemical and biological. The response variables used to determine the effects of fish farm effluent on water quality vary considerably, yet most studies indicate that aquaculture negatively affects the environment. Overall, we highlight the knowledge gaps, including a lack of studies in freshwater aquaculture hotspots. The effects of fish farming on bacterial communities are also not clear due to limited research on these bioindicators. We suggest improvements in study design, including thorough consideration of confounding factors, and the provision of background information on the fish farms.

Economic Viability of Aquaponics Across Global Climate Zones: A Meta‐Analytical Assessment - Ewumi Azeez Folorunso; Radek Gebauer; Jan Mraz (Reviews in Aquaculture, 2026)
Aquaponic systems are emerging as sustainable agricultural solutions that conserve water and recycle waste, enabling food cultivation in urban, rural, and arid regions. They are increasingly advocated across diverse contexts, yet adoption remains limited due to concerns about economic viability stemming from huge capital investment and low profitability. In this study, we employed a metadata analysis to assess the influence of climate zones and system configurations on the profitability of soilless systems. Our findings informed the development of a data‐based support tool—APECO—presented as a prototype that uses compiled metadata. Productivity in tropical climates (Aw and Am) was associated with lower energy and labor costs, which corresponded with comparatively better outcomes than temperate regions in terms of breakeven price, net return, and payback periods. However, these patterns should be interpreted with caution due to dataset imbalance, as approximately one‐third of studies were conducted in the Aw climate zone, while data from other zones were sparse. Profitability also appeared to vary between configurations, but the observed divergence between coupled (revenue‐linked) and decoupled (cost‐linked) aquaponics should be regarded as preliminary, given that only 9% of the dataset represented decoupled systems. Plant revenue and fish yield were most strongly associated with net returns across climates, suggesting that context‐specific productivity gains may play an essential role in shaping profitability. We introduced APECO as a proof‐of‐concept calculator designed to integrate system‐specific metadata with user inputs; however, as it has not yet been validated with real‐world data, its use should be regarded as illustrative, pending empirical validation.

Diversification of Aquaculture Production in Relation to Global Change: The Case of the Domestication of Indigenous Euryhaline Catfish Species (Siluriformes) in the Mekong River Delta, Viet Nam - Nguyen Tinh Em; Nguyen Thanh Phuong; Bui Thi Bich Hang; Duong Thuy Yen; Le Quoc Viet; Do Thi Thanh Huong; Vo Nam Son; Huynh Viet Khai; Nguyen Hong Quyet Thang; Nguyen Tan Tai; Fabrice Teletchea; Frédéric Clota; et al. (Reviews in Aquaculture, 2026)
The Mekong River Delta, the heart of Vietnam's aquaculture industry, is facing many challenges due to climate change, particularly salinity intrusion. In this context, this review aimed to assess the potential of indigenous euryhaline catfish species to diversify fish farming, strengthen food security, and build resilience in the region. Among the 1219 fish species recorded in the Lower Mekong Basin, 176 belong to the order siluriformes. Using a selection framework based on biological, ecological, market demand, and Aquaculture Readiness Levels criteria, 18 euryhaline catfish species were selected and analysed, with Pangasius krempfi , Pangasius mekongensis , Mystus gulio , and Plotosus canius emerging as the most promising candidates. These selected species are currently in the early phases of domestication and face key challenges. Of the four species, P. krempfi and P. mekongensis show high market value but are hindered by unreliable seed supply and significant knowledge gaps in breeding and other farming protocols. M. gulio appears as a promising candidate with already established reproduction techniques, though improvements in grow‐out practices are required, while P. canius requires further research on artificial breeding and feeding optimization. For future developments, it is crucial to establish standardized hatchery protocols, broodstock management, improved farming practices, and species‐specific formulated feeds. Additionally, as native species are locally consumed, implementing market‐driven strategies is essential to increase profitability and ensure long‐term sustainability.

Correction to “Recent Advances in the Functional Roles of Non‐Coding RNAs in Pancrustacea” (Reviews in Aquaculture, 2026)