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Publications

Publications from the Alaska Science Center.

Filter Total Items: 2918

Elodea mediates juvenile salmon growth by altering physical structure in freshwater habitats

Invasive species introductions in high latitudes are accelerating and elevating the need to address questions of their effects on Subarctic and Arctic ecosystems. As a driver of ecosystem function, submerged aquatic vegetation is one of the most deleterious biological invasions to aquatic food webs. The aquatic plant Elodea spp. has potential to be a widespread invader to Arctic and Subarctic ecos
Authors
Michael P. Carey, Gordon H. Reeves, Suresh Sethi, Theresa L. Tanner, Daniel B. Young, Krista K. Bartz, Christian E. Zimmerman

Survey for selected parasites in Alaska brown bears (Ursus arctos)

To assess infection with or exposure to endo- and ectoparasites in Alaska brown bears (Ursus arctos), blood and fecal samples were collected during 2013–17 from five locations: Gates of the Arctic National Park and Preserve; Katmai National Park; Lake Clark National Park and Preserve; Yakutat Forelands; and Kodiak Island. Standard fecal centrifugal flotation was used to screen for gastrointestinal
Authors
Ellen Haynes, Sarah Coker, Michael J. Yabsley, Kevin Niedrighaus, Andrew M. Ramey, Guilherme Verocai, Grant Hilderbrant, Kyle Joly, Dave Gustine, Buck Mangipane, William Leacock, Anthony P. Crupi, Christopher A. Cleveland

High winds and melting sea ice trigger landward movement in a polar bear population of concern

Some animal species are responding to climate change by altering the timing of events like mating and migration. Such behavioral plasticity can be adaptive, but it is not always. Polar bears (Ursus maritimus) from the southern Beaufort Sea subpopulation have mostly remained on ice year-round, but as the climate warms and summer sea ice declines, a growing proportion of the subpopulation is summeri
Authors
Annie Kellner, Todd C. Atwood, David C. Douglas, Stewart Breck, George Wittemyer

eDNA Metabarcoding Analyses of Diet in Yellow-Billed Loons of Northern Alaska

Environmental DNA is a burgeoning tool used to address wide-ranging scientific questions, including determining diets of difficult-to-sample predators. Loons are large piscivorous diving birds that capture and consume prey underwater, making it nearly impossible to visually determine their diet via observation alone. Identifying species' diets is important for understanding basic life history trai
Authors
Damian M. Menning, Brian D. Uher-Koch, Melanie J. Flamme, Trey Simmons, Joel Schmutz, Sandra Talbot

Peak Cenozoic warmth enabled deep-sea sand deposition

The early Eocene (~ 56–48 million years ago) was marked by peak Cenozoic warmth and sea levels, high CO2, and largely ice-free conditions. This time has been described as a period of increased continental erosion and silicate weathering. However, these conclusions are based largely on geochemical investigation of marine mudstones and carbonates or study of intermontane Laramide basin settings. Her
Authors
Zachary FM Burton, Tim McHargue, Christopher H. Kremer, Richard B Bloch, Jared T. Gooley, Chayawan Jailka, Jake Harrington, Stephan A. Graham

Increasing Alaskan river discharge during the cold season is driven by recent warming

Arctic hydrology is experiencing rapid changes including earlier snow melt, permafrost degradation, increasing active layer depth, and reduced river ice, all of which are expected to lead to changes in stream flow regimes. Recently, long-term (>60 years) climate reanalysis and river discharge observation data have become available. We utilized these data to assess long-term changes in discharge an
Authors
D Blaskey, Joshua C. Koch, M. Gooseff, A. C. Newman, Yang Cheng, Jonathan A. O'Donnell, K Musselman

Joint spatiotemporal models to predict seabird densities at sea

Introduction: Seabirds are abundant, conspicuous members of marine ecosystems worldwide. Synthesis of distribution data compiled over time is required to address regional management issues and understand ecosystem change. Major challenges when estimating seabird densities at sea arise from variability in dispersion of the birds, sampling effort over time and space, and differences in bird detectio
Authors
Mayumi L. Arimitsu, John F. Piatt, James Thorson, Kathy Kuletz, Gary Drew, Sarah K. Schoen, Dan Cushing, Caitlin Kroeger, William Sydeman

Fecal DNA metabarcoding shows credible short-term prey detections and explains variation in the gut microbiome of two polar bear subpopulations

This study developed and evaluated DNA metabarcoding to identify the presence of pinniped and cetacean prey DNA in fecal samples of East Greenland (EG) and Southern Beaufort Sea (SB) polar bears Ursus maritimus sampled in the spring of 2015-2019. Prey DNA was detected in half (49/92) of all samples, and when detected, ringed seal Pusa hispida was the predominant prey species, identified in 100% (2
Authors
Megan Franz, L Whyte, Todd C. Atwood, Damian M. Menning, Sarah A. Sonsthagen, Sandra Talbot, Kristin L. Laidre, Emmanuel Gonzalez, Melissa McKinney

Adult spawners: A critical period for subarctic Chinook salmon in a changing climate

Concurrent, distribution-wide abundance declines of some Pacific salmon species, including Chinook salmon (Oncorhynchus tshawytscha), highlights the need to understand how vulnerability at different life stages to climate stressors affects population dynamics and fisheries sustainability. Yukon River Chinook salmon stocks are among the largest subarctic populations, near the northernmost extent of
Authors
Kathrine G. Howard, Vanessa R. von Biela

Recent history of glacial lake outburst floods, analysis of channel changes, and development of a two-dimensional flow and sediment transport model of the Snow River near Seward, Alaska

Snow Lake, a glacially dammed lake on the Snow Glacier near Seward, Alaska, drains rapidly every 14 months–3 years, causing flooding along the Snow River. Highway, railroad, and utility infrastructure on the lower Snow River floodplain is vulnerable to flood damage. Historical hydrology, geomorphology, and two-dimensional hydraulic and sediment transport modeling were used to assess the flood risk
Authors
Robin A. Beebee

Three-decades of Rocky Intertidal Photo Series Documenting interannual variability in western Prince William Sound

During summer 2021 we re-visited and re-photographed intertidal community scenes at seven rocky intertidal sites in Western Prince William Sound, adding another year of photos to a 32-year monitoring effort. The sites include both previously-oiled and un-oiled locations that were the subject of repeated annual photos beginning in 1990, one year after the March 24, 1989 Exxon Valdez Oil Spill. Phot
Authors
Alan Mearns, Dave Janka, Scott Pegau, Robert Campbell, Brian H. Robinson

Polar bear research in a changing arctic

No abstract available
Authors
Todd C. Atwood