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Publications

USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.

Filter Total Items: 2889

Genetic variation in sea otters (Enhydra lutris) from the North Pacific with relevance to the threatened Southwest Alaska Distinct Population Segment

For the sea otter (Enhydra lutris), genetic population structure is an area of research that has not received significant attention, especially in Southwest Alaska where that distinct population segment has been listed as threatened since 2005 pursuant to the U.S. Endangered Species Act. In this study, 501 samples from 14 locations from Prince William Sound, Alaska to the Commander Islands in Russ
Authors
Blair G. Flannery, Ora L. Russ, Michelle St. Martin, William S. Beatty, Kristen Worman, Joel Garlich-Miller, Verena A. Gill, Patrick R. Lemons, Daniel Monson, Kimberly A. Kloecker, Daniel Esler, John Wenburg

Life-history attributes of Arctic-breeding birds drive uneven responses to environmental variability across different phases of the reproductive cycle

Animals exhibit varied life-history traits that reflect adaptive responses to their environments. For Arctic-breeding birds, traits related to diet, egg nutrient allocation, clutch size, and chick growth are predicted to be under increasing selection pressure due to rapid climate change and increasing environmental variability across high-latitude regions. We compared four migratory birds (black b
Authors
Daniel R. Ruthrauff, Vijay P. Patil, Jerry W. Hupp, David H. Ward

Subsurface swimming and stationary diving are metabolically cheap in adult Pacific walruses (Odobenus rosmarus divergens)

Walruses rely on sea-ice to efficiently forage and rest between diving bouts while maintaining proximity to prime foraging habitat. Recent declines in summer sea ice have resulted in walruses hauling out on land where they have to travel farther to access productive benthic habitat while potentially increasing energetic costs. Despite the need to better understand the impact of sea ice loss on ene
Authors
Alicia Borque-Espinosa, Karyn D. Rode, Diana Ferrero-Fernandex, Anabel Forte, Romana Capaccioni-Azzati, Andreas Fahlman

Changing impacts of Alaska-Aleutian subduction zone tsunamis in California under future sea-level rise

The amplification of coastal hazards such as distant-source tsunamis under future relative sea-level rise (RSLR) is poorly constrained. In southern California, the Alaska-Aleutian subduction zone has been identified as an earthquake source region of particular concern for a worst-case scenario distant-source tsunami. Here, we explore how RSLR over the next century will influence future maximum nea
Authors
Tina Dura, Andra Garner, Robert Weiss, Robert E. Kopp, Simon E. Engelhart, Robert C. Witter, Richard W. Briggs, Charles Mueller, Alan Nelson, Benjamin P. Horton

Mismatch-induced growth reductions in a clade of Arctic-breeding shorebirds are rarely mitigated by increasing temperatures

In seasonal environments subject to climate change, organisms typically show phenological changes. As these changes are usually stronger in organisms at lower trophic levels than those at higher trophic levels, mismatches between consumers and their prey may occur during the consumers’ reproduction period. While in some species a trophic mismatch induces reductions in offspring growth, this is not
Authors
Thomas Lameris, Pavel S. Tomkovich, James A. Johnson, R.I. Guy Morrison, Lucas Decicco, Maksim N. Dementyev, Ingrid Tulp, Simeon Lisovski, Robert E. Gill, Job ten Horn, Theunis Piersma, Z. Pohlen, Hans Schekkerman, Mikhail Soloviev, E. Syroechkovsky, Mikhail Zhemchuzhnikov, Jan A. van Gils

Diet-driven mercury contamination is associated with polar bear gut microbiota

The gut microbiota may modulate the disposition and toxicity of environmental contaminants within a host but, conversely, contaminants may also impact gut bacteria. Such contaminant-gut microbial connections, which could lead to alteration of host health, remain poorly known and are rarely studied in free-ranging wildlife. The polar bear (Ursus maritimus) is a long-lived, wide-ranging apex predato
Authors
Sophie Watson, Melissa McKinney, Massimo Pindo, Matthew Bull, Todd C. Atwood, Heidi Hauffe, Sarah Perkins

Knowledge gaps update to the 2019 IPCC special report on the ocean and cryosphere: Prospects to refine coastal flood hazard assessments and adaptation strategies with at-risk communities of Alaska

This article reviews the status of knowledge gaps and co-production process challenges that impede coastal flood hazard resilience planning in communities of northwestern Alaska, where threat levels are high. Discussion focuses on the state of knowledge arising after preparation of the 2019 IPCC Special Report on the Ocean and Cryosphere in a Changing Climate and highlights prospects to address ur
Authors
Dee Williams, Li H. Erikson

Bar-tailed Godwits Limosa lapponica in Alaska: Revisiting population estimates from the staging grounds

Bar-tailed Godwits Limosa lapponica baueri breed in Alaska and spend the nonbreeding season primarily in eastern Australia and New Zealand. Long-term declines spurred recent surveys at nonbreeding sites that yielded a revised population estimate of ~126,000 godwits. We conducted aerial surveys for Bar-tailed Godwits in 2018 and 2019 at pre-migratory staging sites in western Alaska. Counts from sim
Authors
Daniel R. Ruthrauff, Zak Pohlen, Heather M. Wilson, James Johnson

Bedrock gorge incision via anthropogenic meander cutoff

Bedrock river-gorge incision represents a fundamental landscape-shaping process, but a dearth of observational data at >10 yr timescales impedes understanding of gorge formation. I quantify 102 yr rates and processes of gorge incision using historical records, field observations, and topographic and image analysis of a human-caused bedrock meander cutoff along the North Fork Fortymile River in Ala
Authors
Adrian Bender

New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos)

Although polar bears (Ursus maritimus) and brown bears (U. arctos) have been exhibited in zoological gardens for centuries, little is known about their nutritional needs. Multiple recent studies on both wild and captive polar bears and brown bears have found that they voluntarily select dietary macronutrient proportions resulting in much lower dietary protein and higher fat or digestible carbohydr
Authors
Charles T. Robbins, Troy N Tollefson, Karyn D. Rode, Joy Erlenbach, Amanda J. Ardente

South Africa's experimental fisheries closures and recovery of the endangered African penguin

In a scientifically-transformative project, South Africa implemented a decade-long field experiment to understand how fisheries may be affecting its most iconic seabird, the African penguin Spheniscus demersus. This unique effort prohibits the take of anchovy and sardine within relatively small areas around four African penguin breeding colonies, two in the Benguela upwelling ecosystem and two in
Authors
William J. Sydeman, George L. Hunt, E.K. Pikitch, Julia K. Parrish, John F. Piatt, P Dee Boersma, Les Kaufman, Daniel W. Anderson, Sarah Ann Thompson, Richard B. Sherley

Long-term variation in polar bear body condition and maternal investment relative to a changing environment

In the Arctic, warming air and ocean temperatures have resulted in substantial changes to sea ice, which is primary habitat for polar bears (Ursus maritimus). Reductions in extent, duration, and thickness have altered sea ice dynamics, which influences the ability of polar bears to reliably access marine mammal prey. Because nutritional condition is closely linked to population vital rates, a prog
Authors
Todd C. Atwood, Karyn D. Rode, David C. Douglas, Kristin S. Simac, Anthony Pagano, Jeffrey F. Bromaghin
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