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Waterfowl Move Less in Heterogeneous and Human‐Populated Landscapes, With Implications for Spread of Avian Influenza VirusesNARA Subscribed
Animal movements contribute to the spread of infectious diseases and are driven in part by environmental conditions. We investigated the links among the environment, animal movement, and infectious disease dynamics in waterfowl, which are among the primary wildlife hosts of avian influenza viruses. By combining telemetry data on 4606 individuals from 26 waterfowl species with data on land cover, weather, and vegetation, we fou...
Using DNA metabarcoding, we examined diet composition, prey resources, and saxitoxin (STX) and parasite exposure in Steller sea lions (SSL) in the Gulf of Alaska in July and October 2022–2023 using 251 scat samples and 45 seawater samples. Using 12S rRNA MiFish gene metabarcoding, diet items in Prince William Sound (PWS), Cook Inlet and near Kodiak ordered by prevalence were salmon, gadids, herring, flatfishes and capelin. Usi...
In August 2024, a northern fur seal mortality event was observed on St. Paul Island, AK in the southeast (SE) Bering Sea. Ten seals in good body condition were found dead along with large accumulations of dead fish on Benson Beach located on St. Paul Island. Full necropsies of the five available adult seals, one pup, and several fish did not reveal any overt causes of death. Testing of tissues for the algal neurotoxins domoic...
Bird migration on the edge: Experimental manipulation of corticosterone advances departure datesNARA Subscribed
Endogenous reserves accumulated during migration stopovers help most migratory birds cope with environmental uncertainties and fuel energy demands associated with migration and/or reproduction. Migratory decisions, such as departure time, should thus be finely tuned to energy intake rate at stopover sites. However, the physiological drivers of these decisions remain poorly understood. Glucocorticoids such as corticosterone (CO...
The biomass of mesopelagic fishes is estimated to be on the order of or to exceed that of fishes in the epipelagic. Despite their abundance and importance as an ecological link between surface and deep ocean habitats, there is a dearth of basic life history data for mesopelagic fishes. Reproductive biology data are critical for understanding population dynamics and estimating production of a species, particularly when age and...
The Tara Microplastics mission was conducted for 7 months to investigate plastic pollution along nine major rivers in Europe—Thames, Elbe, Rhine, Seine, Loire, Garonne, Ebro, Rhone, and Tiber. An extensive suite of sampling protocols was applied at four to five sites on each river along a salinity gradient from the sea and the outer estuary to downstream and upstream of the first heavily populated city. Biophysicochemical para...
Ice seals as sentinels for algal toxin presence in the Pacific Arctic and subarctic marine ecosystemsNARA Subscribed
Domoic acid (DA) and saxitoxin (STX)‐producing algae are present in Alaskan seas, presenting exposure risks to marine mammals that may be increasing due to climate change. To investigate potential increases in exposure risks to four pagophilic ice seal species ( Erignathus barbatus , bearded seals; Pusa hispida , ringed seals; Phoca largha , spotted seals; and Histriophoca fasciata , ribbon seals), this study analyzed samples...
Qualifying and quantifying nutrient flows within open‐water Integrated Multi‐Trophic Aquaculture ( IMTA ) systems is necessary to determine transfer efficiencies and to assess overall system performance. There are numerous empirical performance metrics, such as spatially defined growth and nutrient sequestration, which may have application. When used in combination with modelling techniques, empirical approaches can be a power...
Landscape ecology plays a vital role in understanding the impacts of land‐use change on biodiversity, but it is not a predictive discipline, lacking theoretical models that quantitatively predict biodiversity patterns from first principles. Here, we draw heavily on ideas from phylogenetics to fill this gap, basing our approach on the insight that habitat fragments have a shared history. We develop a landscape ‘terrageny’, whic...
Coccolithophores are unicellular phytoplankton that produce calcium carbonate coccoliths as an exoskeleton. E miliania huxleyi , the most abundant coccolithophore in the world's ocean, plays a major role in the global carbon cycle by regulating the exchange of CO 2 across the ocean‐atmosphere interface through photosynthesis and calcium carbonate precipitation. As CO 2 concentration is rising in the atmosphere, the ocean is ac...
Anthropogenic understory fires affect large areas of tropical forest, particularly during severe droughts. Yet, the mechanisms that control tropical forests' susceptibility to fire remain ambiguous. We tested the widely accepted hypothesis that Amazon forest fires increase susceptibility to further burning by conducting a 150 ha fire experiment in a closed‐canopy forest near the southeastern Amazon forest–savanna boundary. For...
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