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The construction of a predictive theory of the dynamics and structure of microbial communities requires the identification of repeatable, robust empirical patterns. The investigation of such patterns in ecology has historically been the domain of the subdiscipline macroecology . However, the application of macroecology to microorganisms is not straightforward, as we lack an understanding of how microbial macroecology stems fro...
An Overview of Vaccine Development Strategies for Columnaris‐Causing Bacteria in Cultured FishNARA Subscribed
Columnaris disease, caused by columnaris‐causing bacteria (CCB), affects cultured and wild freshwater fish worldwide. Belonging to the phylum Bacteroidota and the family Flavobacteriaceae, CCB are gram‐negative, yellow‐pigmented bacteria that are presumed ubiquitous in freshwater habitats. Since the first report of the disease in 1922, growth and survival, pathogenesis, and transmission of these pathogens have been intensely r...
Effects of Disturbance and Fertilisation on Plant Community Synchrony, Biodiversity and Stability Through SuccessionNARA Subscribed
Global change drivers alter multiple components of community composition, with cascading impacts on ecosystem stability. However, it remains largely unknown how interactions among global change drivers will alter community synchrony, especially across successional timescales. We analysed a 22‐year time series of grassland community data from Cedar Creek, USA, to examine the joint effects of pulse soil disturbance and press nit...
Channel catfish ( Ictalurus punctatus ) and Nile tilapia ( Oreochromis niloticus ) are two aquaculture species of great importance. Intensive production is often hindered by poor growth performance and disease mortality. The aim of this study was to evaluate the potential of a commercial fermented yeast product, DVAQUA, on channel catfish and Nile tilapia growth performance metrics and disease resistance. Channel catfish and N...
Pathways from research to sustainable development: Insights from ten research projects in sustainability and resilienceNARA Subscribed
Drawing on collective experience from ten collaborative research projects focused on the Global South, we identify three major challenges that impede the translation of research on sustainability and resilience into better-informed choices by individuals and policy-makers that in turn can support transformation to a sustainable future. The three challenges comprise: (i) converting knowledge produced during research projects in...
Restoration ecology through the lens of coexistence theoryNARA Subscribed
Probiotics enhance resistance to Streptococcus iniae in Nile tilapia ( Oreochromis niloticus ) reared in biofloc systemsNARA Subscribed
Biofloc technology is a rearing technique that maintains desired water quality by manipulating carbon and nitrogen and their inherent mixture of organic matter and microbes. Beneficial microorganisms in biofloc systems produce bioactive metabolites that may deter the growth of pathogenic microbes. As little is known about the interaction of biofloc systems and the addition of probiotics, this study focused on this integration...
Quantifying mechanisms of coexistence in disease ecologyNARA Subscribed
Pathogen coexistence depends on ecological processes operating at both within and between‐host scales, making it difficult to quantify which processes may promote or prevent coexistence. Here, we propose that adapting modern coexistence theory—traditionally applied in plant communities—to pathogen systems provides an exciting approach for examining mechanisms of coexistence operating across different spatial scales. We first o...
It is well known that species interactions between exotic and native species are important for determining the success of biological invasions and how influential exotic species become in invaded communities. The strength and type of interactions between species can substantially vary, however, from negative and detrimental to minimal or even positive. Increasing evidence from the literature shows that exotic species have posi...
Accounting for demographic uncertainty increases predictions for species coexistence: A case study with annual plantsNARA Subscribed
Natural systems contain more complexity than is accounted for in models of modern coexistence theory. Coexistence modelling often disregards variation arising from stochasticity in biological processes, heterogeneity among individuals and plasticity in trait values. However, these unaccounted‐for sources of uncertainty are likely to be ecologically important and have the potential to impact estimates of coexistence. We applied...
Methane (CH 4 ), a potent greenhouse gas, is the second most important greenhouse gas contributor to climate change after carbon dioxide (CO 2 ). The biological emissions of CH 4 from wetlands are a major uncertainty in CH 4 budgets. Microbial methanogenesis by Archaea is an anaerobic process accounting for most biological CH 4 production in nature, yet recent observations indicate that large emissions can originate from oxyge...
Ecological stability refers to a family of concepts used to describe how systems of interacting species vary through time and respond to disturbances. Because observed ecological stability depends on sampling scales and environmental context, it is notoriously difficult to compare measurements across sites and systems. Here, we apply stochastic dynamical systems theory to derive general statistical scaling relationships across...
Stochasticity is a core component of ecology, as it underlies key processes that structure and create variability in nature. Despite its fundamental importance in ecological systems, the concept is often treated as synonymous with unpredictability in community ecology, and studies tend to focus on single forms of stochasticity rather than taking a more holistic view. This has led to multiple narratives for how stochasticity me...
Influence of native catfish mucus on Flavobacterium columnare growth and proteolytic activityNARA Subscribed
Flavobacterium columnare causes columnaris disease of farmed and wild freshwater fish. Skin mucus is an important factor in early stages of columnaris pathogenesis, albeit little studied. Our objectives were to (a) characterize the terminal glycosylation pattern ( TGP ) of catfish mucus, (b) determine the growth of F. columnare in formulated water ( FW )‐containing channel catfish ( Ictalurus punctatus ) or hybrid catfish ( Ic...
Columnaris disease can be problematic in tilapia ( O reochromis spp.) production. An understanding of the pathogenesis and virulence of F lavobacterium columnare is needed to develop prevention strategies. The objective of this study was to determine the virulence of genetically defined isolates of F . columnare in sex‐reversed hybrid tilapia, O reochromis niloticus ( L .) × O . aureus ( S teindachner). A series of immersion c...
Intragenomic heterogeneity in the 16 S r RNA genes of F lavobacterium columnare and standard protocol for genomovar assignmentNARA Subscribed
Genetic variability in 16 S r RNA gene sequences has been demonstrated among isolates of F lavobacterium columnare, and a restriction fragment length polymorphism ( RFLP ) assay is available for genetic typing of this important fish pathogen. Interpretation of restriction patterns can be difficult due to the lack of a formal description of the expected number and sizes of DNA fragments generated for each of the described genom...
For decades conservation biologists have proposed general rules of thumb for minimum viable population size (MVP); typically, they range from hundreds to thousands of individuals. These rules have shifted conservation resources away from small and fragmented populations. We examined whether iteroparous, long‐lived species might constitute an exception to general MVP guidelines. On the basis of results from a 10‐year capture‐re...
Streptococcus iniae is a significant pathogen impacting aquaculture production worldwide. The objectives of this study were to determine whether a developed modified S. iniae (ARS‐98‐60) bacterin vaccine is efficacious in Nile tilapia, Oreochromis niloticus (L.), against challenge with heterologous isolates from diverse geographical locations and to evaluate protein and antigenic variability among the isolates tested. Two grou...