Elodea mediates juvenile salmon growth by altering physical structure in freshwater habitats
Michael P. Carey, Gordon H. Reeves, Suresh Sethi, Theresa L. Tanner, Daniel B. Young, Krista K. Bartz, Christian E. Zimmerman
2023, Biological Invasions (25) 1509-1525
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...
Survey for selected parasites in Alaska brown bears (Ursus arctos)
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
2023, Journal of Wildlife Diseases (59) 186-191
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...
High winds and melting sea ice trigger landward movement in a polar bear population of concern
Annie Kellner, Todd C. Atwood, David C. Douglas, Stewart Breck, George Wittemyer
2023, Ecosphere (14)
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...
eDNA Metabarcoding Analyses of Diet in Yellow-Billed Loons of Northern Alaska
Damian M. Menning, Brian D. Uher-Koch, Melanie J. Flamme, Trey Simmons, Joel Schmutz, Sandra Talbot
2023, Waterbirds (45) 159-166
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...
Peak Cenozoic warmth enabled deep-sea sand deposition
Zachary FM Burton, Tim McHargue, Christopher H. Kremer, Richard B Bloch, Jared T. Gooley, Chayawan Jailka, Jake Harrington, Stephan A. Graham
2023, Scientific Reports (13)
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...
Declines in body size of sockeye salmon associated with increased competition in the ocean
Jan Ohlberger, Timothy Joseph Cline, Daniel Schindler, Bert Lewis
2023, Proceedings of the Royal Society B (290)
Declining body sizes have been documented for several species of Pacific salmon; however, whether size declines are caused mainly by ocean warming or other ecological factors, and whether they result primarily from trends in age at maturation or changing growth rates remain poorly understood. We quantified changes in mean body...
Increasing Alaskan river discharge during the cold season is driven by recent warming
D Blaskey, Joshua C. Koch, M. Gooseff, A. C. Newman, Yang Cheng, Jonathan A. O'Donnell, K Musselman
2023, Environmental Research Letters (18)
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....
Ice and ocean constraints on early human migrations into North America along the Pacific Coast
Summer K. Praetorius, Jay R. Alder, Alan Condron, Alan Mix, Maureen Walczak, Beth Elaine Caissie, Jon Erlandson
2023, Proceedings of the National Academy of Sciences (120)
Founding populations of the first Americans likely occupied parts of Beringia during the Last Glacial Maximum (LGM). The timing, pathways, and modes of their southward transit remain unknown, but blockage of the interior route by North American ice sheets between ~26 and 14 cal kyr BP (ka) favors a coastal...
Dating individual zones in phenocrysts from the 2016–2017 eruption of Bogoslof volcano provides constraints on timescales of magmatic processes
Jamshid Moshrefzadeh, Pavel Izbekof, Matthew W. Loewen, Jessica Larsen, Sean P. Regan
2023, Journal of Volcanology and Geothermal Research (435)
We investigate the rates of magmatic processes using clinopyroxene diffusion chronometry on volcanic products erupted in August 2017 at the end of the 9-month eruption of Bogoslof volcano. The eruptive products contain plagioclase, clinopyroxene, and amphibole, all of which exhibit sharp chemical boundaries...
Joint spatiotemporal models to predict seabird densities at sea
Mayumi L. Arimitsu, John F. Piatt, James Thorson, Kathy Kuletz, Gary Drew, Sarah K. Schoen, Dan Cushing, Caitlin Kroeger, William Sydeman
2023, Frontiers in Marine Science (10)
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...
Revising supraglacial rock avalanche magnitudes and frequencies in Glacier Bay National Park, Alaska
William Smith, Stuart A. Dunning, Neil Ross, Jon Telling, Erin K. Bessette-Kirton, Dan H. Shugar, Jeffrey A. Coe, M. Geertsema
2023, Geomorphology (425)
The frequency of large supraglacial landslides (rock avalanches) occurring in glacial environments is thought to be increasing due to feedbacks with climate warming and permafrost degradation. However, it is difficult to (i) test this; (ii) establish cause–effect relationships; and (iii) determine...
Fecal DNA metabarcoding shows credible short-term prey detections and explains variation in the gut microbiome of two polar bear subpopulations
Megan Franz, L Whyte, Todd C. Atwood, Damian M. Menning, Sarah A. Sonsthagen, Sandra Talbot, Kristin L. Laidre, Emmanuel Gonzalez, Melissa McKinney
2023, Marine Ecology Progress Series (MEPS) (704) 131-147
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...
Adult spawners: A critical period for subarctic Chinook salmon in a changing climate
Kathrine G. Howard, Vanessa R. von Biela
2023, Global Change Biology (29) 1759-1773
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...
Moving Aircraft River Velocimetry (MARV): Framework and proof-of-concept on the Tanana River
Carl J. Legleiter, Paul J. Kinzel, Mark Laker, Jeff Conaway
2023, Water Resources Research (59)
Information on velocity fields in rivers is critical for designing infrastructure, modeling contaminant transport, and assessing habitat. Although non-contact approaches to measuring flow velocity are well established, these methods assume a stationary imaging platform. This study eliminates this constraint by introducing a framework for moving aircraft river...
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
Robin A. Beebee
2023, Scientific Investigations Report 2022-5099
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...
Geologic map of Okmok Volcano
Jessica Larsen, Christina A. Neal, Janet Schaefer, Christopher J. Nye
2023, Report of Investigations of the Alaska Department of Natural Resources, Division of Geological & Geophysical Surveys 2023-1
The geologic map and description of map units presented here cover approximately 880 km2 of northeastern Umnak Island, Aleutian Islands, Alaska. This report focuses on Okmok Volcano and its eruptive products and updates the mid-20th-century geologic map of Byers (1959). Mapped deposits reflect the state of the volcano just prior...
Trace elements in blood of sea ducks from Dutch Harbor and Izembek Lagoon, Alaska
J. Christian Franson, Tuula E. Hollmen, Paul L. Flint, Angela C. Matz
2023, Journal of Fish and Wildlife Management (14) 41-50
In 2001, we collected whole blood from sea ducks (Steller’s eider Polysticta stelleri, harlequin duck Histrionicus histrionicus, black scoter Melanitta nigra, and long-tailed duck Clangula hyemalis) wintering at Dutch Harbor, Alaska, and from Steller’s eiders molting at Izembek Lagoon on the Alaska Peninsula....
Borealization of nearshore fishes on an interior Arctic shelf over multiple decades
Vanessa R. von Biela, Sarah M. Laske, Ashley E. Stanek, Randy J Brown, Kenneth H. Dunton
2023, Global Change Biology (29) 1822-1838
Borealization is a type of community reorganization where Arctic specialists are replaced by species with more boreal distributions in response to climatic warming. The process of borealization is often exemplified by the northward range expansions and subsequent proliferation of boreal species on the Pacific and Atlantic...
Investigating effects of climate-induced changes in water temperature and diet on mercury concentrations in an Arctic freshwater forage fish
Sarah M. Laske, Samantha M. Burke, Michael P. Carey, Heidi K. Swanson, Christian E. Zimmerman
2023, Environmental Research (218)
The amount of mercury (Hg) in Arctic lake food webs is, and will continue to be, affected by rapid, ongoing climate change. At warmer temperatures, fish require more energy to sustain growth; changes in their metabolic rates and consuming prey with potentially higher Hg concentrations could result in increased Hg...
Hydrologic and landscape controls on dissolved organic matter composition across western North American Arctic lakes
Martin R. Kurek, Fenix Garcia-Tigreros, Kimberly Wickland, Karen E. Frey, Mark Dornblaser, Robert G. Striegl, Sydney F. Niles, Amy M. McKenna, Pieter J.K Aukes, Ethan D. Kyzivat, Chao Wang, Tamlin M. Pavelsky, Laurence C. Smith, Sherry L. Schiff, David Butman, Robert G.M. Spencer
2023, Global Biogeochemical Cycles (37)
Northern high-latitude lakes are hotspots for cycling dissolved organic carbon (DOC) inputs from allochthonous sources to the atmosphere. However, the spatial distribution of lake dissolved organic matter (DOM) is largely unknown across Arctic-boreal regions with respect to the surrounding landscape. We expand on regional studies of northern...
Lava-ice interactions during historical eruptions of Veniaminof Volcano, Alaska and the potential for meltwater floods and lahars
Christopher F. Waythomas, Benjamin R Edwards, Thomas P Miller, Robert G. McGimsey
2023, Natural Hazards (115) 73-106
Veniaminof Volcano on the Alaska Peninsula of southwest Alaska is one of a small group of ice-clad volcanoes globally that erupts lava flows in the presence of glacier ice. Here, we describe the nature of lava-ice-snow interactions that have occurred during historical eruptions of the volcano since 1944. Lava flows...
Efficacy of bear spray as a deterrent against polar bears
James Wilder, Lindsey Mangipane, Todd C. Atwood, Anatoly A. Kochnev, Tom Smith, Dag Vongraven
2023, Wildlife Society Bulletin (47)
Although there have been few attempts to systematically analyze information on the use of deterrents on polar bears (Ursus maritimus), understanding their effectiveness in mitigating human-polar bear conflicts is critical to ensuring both human safety and polar bear conservation. To fill this knowledge gap, we analyzed...
Optimizing surveys of fall-staging geese using aerial imagery and automated counting
Emily L. Weiser, Paul L. Flint, Dennis K Marks, Brad S Shults, Heather M. Wilson, Sarah J. Thompson, Julian B. Fischer
2023, Wildlife Society Bulletin (47)
Ocular aerial surveys allow efficient coverage of large areas and can be used to monitor abundance and distribution of wild populations. However, uncertainty around resulting population estimates can be large due to difficulty in visually identifying and counting animals from aircraft, as well as logistical challenges in estimating detection probabilities....
Partnering in search of answers: Seabird die-offs in the Bering and Chukchi Seas
Robb A. S. Kaler, Gay Sheffield, S Backensto, Jackie Lindsey, T. Jones, J. Parrish, B Ahmasuk, Barbara Bodenstein, Robert J. Dusek, Caroline R. Van Hemert, Matthew M. Smith, P Schwalenberg
2023, Report, Arctic Report Card 2022 (NOAA Technical Report)
Prior to 2015, seabird die-offs in Alaskan waters were rare; they typically occurred in mid-winter, linked to epizootic disease events or above-average ocean temperatures associated with strong El Nino-Southern Oscillation events (Bodenstein et al. 2015, Jones et al. 2019, Romano et al. 2020). Since 2015, the U.S. Fish and Wildlife...
Point count offsets for estimating population sizes of north American landbirds
B.P.M. Edwards, A.C. Smith, T.D.S. Docherety, M.A. Gahbauer, C.R. Gillespie, A.R. Grinde, T. Harmer, D. Iles, Steven M. Matsuoka, N.L. Michel, N.L. Murray, G. Niemi, J. Pasher, D. Pavlacky, B. Robinson, B. Ryder, P. Solymos, D. Stralberg, E.J. Zlonis
2023, Ibis (165) 482-503
Bird monitoring in North America over several decades has generated many open databases, housing millions of structured and semi-structured bird observations. These provide the opportunity to estimate bird densities and population sizes, once variation in factors such as underlying field methods, timing, land cover, proximity to...
