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Exploring Spatial and Temporal Patterns in the Size‐At‐Age of Pacific Halibut in the Gulf of AlaskaNARA Subscribed
Large changes in Pacific halibut ( Hippoglossus stenolepis ) size‐at‐age across decades have affected available fishery yield and management decisions. Characterizing mechanisms driving variability in size‐at‐age of adult Pacific halibut is challenging due to uncertainty associated with spatial and temporal partitioning of the phenomenon. We explored spatial and temporal changes in size‐at‐age structure of Pacific halibut in t...
Remotely Sensed Fire Heterogeneity and Biomass Recovery Predicts Empirical Biodiversity ResponsesNARA Subscribed
Aim To compare field‐based evidence of plant and animal responses to fire with remotely sensed signals of fire heterogeneity and post‐fire biomass recovery. Location South‐eastern Australia; New South Wales. Time Period 2019–2022. Major Taxa Studied A total of 982 species of plants and animals, in eight taxonomic groups: amphibians, birds, fish, insects, mammals, molluscs, plants and reptiles. Methods We collated 545,223 plant...
‘Megafire’—You May Not Like It, But You Cannot Avoid ItNARA Subscribed
Aim The term ‘megafire’ is increasingly used to describe large fires worldwide. We proposed a size‐based definition of megafire—fires exceeding 10,000 ha arising from single or multiple related ignition events. A recent perspective in Global Ecology and Biogeography argues against a size‐based definition of megafire and suggest that the term is too emotive for scientific use. We highlight that many scientific terms originate f...
Grazing herbivores reduce herbaceous biomass and fire activity across African savannasNARA Subscribed
Fire and herbivory interact to alter ecosystems and carbon cycling. In savannas, herbivores can reduce fire activity by removing grass biomass, but the size of these effects and what regulates them remain uncertain. To examine grazing effects on fuels and fire regimes across African savannas, we combined data from herbivore exclosure experiments with remotely sensed data on fire activity and herbivore density. We show that, br...
Identifying historical and future global change drivers that place species recovery at riskNARA Subscribed
Ecosystem management in the face of global change requires understanding how co‐occurring threats affect species and communities. Such an understanding allows for effective management strategies to be identified and implemented. An important component of this is differentiating between factors that are within (e.g. invasive predators) or outside (e.g. drought, large wildfires) of a local manager's control. In the global biodiv...
What do you mean, ‘megafire’?NARA Subscribed
Background ‘Megafire’ is an emerging concept commonly used to describe fires that are extreme in terms of size, behaviour, and/or impacts, but the term’s meaning remains ambiguous. Approach We sought to resolve ambiguity surrounding the meaning of ‘megafire’ by conducting a structured review of the use and definition of the term in several languages in the peer‐reviewed scientific literature. We collated definitions and descri...
Globally, collapse of ecosystems—potentially irreversible change to ecosystem structure, composition and function—imperils biodiversity, human health and well‐being. We examine the current state and recent trajectories of 19 ecosystems, spanning 58° of latitude across 7.7 M km 2 , from Australia's coral reefs to terrestrial Antarctica. Pressures from global climate change and regional human impacts, occurring as chronic ‘press...
Surviving marginalized reefs: assessing the implications of the microbiome on coral physiology and survivorshipNARA Subscribed
Coral reefs are undergoing degradation due to overexploitation, pollution, and climate change. Management and restoration efforts require that we gain a better understanding of the complex interactions between corals, their microbiomes, and their environment. For this purpose, Varadero Reef near Cartagena, Colombia, serves as an informative study system located at the entrance of the Bay of Cartagena adjacent to the Canal del...
Crowdfunding biodiversity conservationNARA Subscribed
Raising funds is critical for conserving biodiversity and hence so is scrutinizing emerging financial mechanisms that may help achieve this goal. Anecdotal evidence indicates crowdfunding is being used to support activities needed for biodiversity conservation, yet its magnitude and allocation remain largely unknown. To help address this knowledge gap, we conducted a global analysis based on conservation‐focused projects extra...
Government agencies faced with politically controversial decisions often discount or ignore scientific information, whether from agency staff or nongovernmental scientists. Recent developments in scientific integrity (the ability to perform, use, communicate, and publish science free from censorship or political interference) in Canada, Australia, and the United States demonstrate a similar trajectory. A perceived increase in...
Fifteen years of quantitative trait loci studies in fish: challenges and future directionsNARA Subscribed
Understanding the genetic basis of phenotypic variation is a major challenge in biology. Here, we systematically evaluate 146 quantitative trait loci ( QTL ) studies on teleost fish over the last 15 years to investigate (i) temporal trends and (ii) factors affecting QTL detection and fine‐mapping. The number of fish QTL studies per year increased over the review period and identified a cumulative number of 3632 putative QTL s....
Landscape‐scale analyses suggest both nutrient and antipredator advantages to Serengeti herbivore hotspotsNARA Subscribed
Mechanistic explanations of herbivore spatial distribution have focused largely on either resource‐related (bottom‐up) or predation‐related (top‐down) factors. We studied direct and indirect influences on the spatial distributions of Serengeti herbivore hotspots, defined as temporally stable areas inhabited by mixed herds of resident grazers. Remote sensing and variation in landscape features were first used to create a map of...
Comparative virulence of Infectious salmon anaemia virus isolates in Atlantic salmon, Salmo salar L.NARA Subscribed
Infectious salmon anaemia virus (ISAV) surveillance in the Bay of Fundy has identified the existence of a large number of genetically distinct ISAV isolates which appear to be of variable virulence. Genetically distinct isolates are currently being designated based on sequencing of the hyper polymorphic region (HPR) of genomic segment 6, which encodes the haemagglutinin–esterase protein, but it has been difficult to elucidate...