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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: 2881

Efficacy of bear spray as a deterrent against polar bears

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 19 incidents involving the use of bear spray on free-ranging polar bears from 1
Authors
James Wilder, Lindsey Mangipane, Todd C. Atwood, Anatoly A. Kochnev, Tom Smith, Dag Vongraven

Optimizing surveys of fall-staging geese using aerial imagery and automated counting

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. Photographic aerial surveys can mitigate
Authors
Emily L. Weiser, Paul L. Flint, Dennis K Marks, Brad S Shults, Heather M. Wilson, Sarah J Thompson, Julian B. Fischer

Partnering in search of answers: Seabird die-offs in the Bering and Chukchi Seas

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 Service (USFWS) has monitored mortality events that have become an
Authors
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

Estimating reproductive and juvenile survival rates when offspring ages are uncertain: A novel multievent mark-resight model with beluga whale case study

Understanding the survival and reproductive rates of a population is critical to determining its long-term dynamics and viability. Mark-resight models are often used to estimate these demographic rates, but estimation of survival and reproductive rates is challenging, especially for wide-ranging, patchily distributed, or cryptic species. In particular, existing mark-resight models cannot accommoda
Authors
Gina K Himes Boor, Tamara L McGuire, Amanda J. Warlick, Rebecca L. Taylor, Sarah J. Converse, John R McClung, Amber D Stephens

Geochemistry and fluxes of gases from hydrothermal features at Newberry Volcano, Oregon, USA

We present the chemical and isotopic compositions of gases and fluxes of CO2 from the hydrothermal features of Newberry Volcano, a large composite volcano located in Oregon's Cascade Range with a summit caldera that hosts two lakes, Paulina and East Lakes. Gas samples were collected from 1982 to 2021 from Paulina Hot Springs (PHS) on the shore of Paulina Lake, East Lake Hot Springs (ELHS) on the s
Authors
Jennifer L. Lewicki, William C. Evans, Steven E. Ingebritsen, Laura E. Clor, Peter J. Kelly, Sara Peek, Robert A. Jensen, Andrew Hunt

Understanding local adaptation to prepare populations for climate change

Adaptation within species to local environments is widespread in nature. Better understanding this local adaptation is critical to conserving biodiversity. However, conservation practices can rely on species’ trait averages or can broadly assume homogeneity across the range to inform management. Recent methodological advances for studying local adaptation provide the opportunity to fine-tune effor
Authors
Mariah H. Meek, Erik A. Beever, Soraia Barbosa, Sarah W. Fitzpatrick, Nicholas K. Fletcher, Cinnamon S. Mittan-Moreau, Brendan N. Reid, Shane C. Campbell-Staton, Nancy Green, Jessica J. Hellmann

Ordovician geology of Alaska

Ordovician rocks, found in northern, east-central, interior and southern Alaska, formed in a variety of depositional and palaeogeographic settings. Shallow- and deep-water strata deposited along the northwestern Laurentian margin occur in east-central Alaska (Yukon River area) and probably correlative rocks crop out to the north in the Porcupine River area. Ordovician strata elsewhere in Alaska ar
Authors
Julie A. Dumoulin, Justin V. Strauss, John Repetski

Brown bear–sea otter interactions along the Katmai coast: Terrestrial and nearshore communities linked by predation

Sea otters were extirpated throughout much of their range by the maritime fur trade in the 18th and 19th centuries, including the coast of Katmai National Park and Preserve in southcentral Alaska. Brown bears are an important component of the Katmai ecosystem where they are the focus of a thriving ecotourism bear-viewing industry as they forage in sedge meadows and dig clams in the extensive tidal
Authors
Daniel Monson, Rebecca L. Taylor, Grant Hilderbrand, Joy Erlenbach, Heather Coletti, James L. Bodkin

Lingering impacts of the 2014-2016 northeast Pacific marine heatwave on seabird demography in Cook Inlet, Alaska (USA)

A protracted period (2014-2016) of anomalously warm water in the northeast Pacific Ocean precipitated an extensive die-off of common murres Uria aalge (hereafter ‘murres’) during 2015-2016, accompanied by reduced colony attendance and reproductive success of murres and black-legged kittiwakes Rissa tridactyla (‘kittiwakes’) starting in 2015. Most murres died of starvation following a large-scale r
Authors
Sarah K. Schoen, Mayumi L. Arimitsu, Caitlin Elizabeth Marsteller, John F. Piatt

Flyway-scale GPS tracking reveals migratory routes and key stopover and non-breeding locations of lesser yellowlegs

Many populations of long-distance migrant shorebirds are declining rapidly. Since the 1970s, the lesser yellowlegs (Tringa flavipes) has experienced a pronounced reduction in abundance of ~63%. The potential causes of the species' decline are complex and interrelated. Understanding the timing of migration, seasonal routes, and important stopover and non-breeding locations used by this species will
Authors
Laura Anne McDuffie, Katherine S. Christie, Audrey R. Taylor, Erica Nol, Christian Friis, Christopher M. Harwood, Jennie Rausch, Benoit Laliberte, Callie Gesmundo, James R. Wright, James A. Johnson

Effects of mass capture on survival of greater white-fronted geese in Alaska

Mass capture of flightless geese during the summer is a common trapping technique to obtain large numbers of individuals for research and marking, but few studies have assessed the impacts of this method on the survival of after-hatch-year geese. We evaluated the effects of holding time and captured flock size on the survival of >26,000 subadult (second yr) and adult (≥third yr) greater white-fron
Authors
Josh Dooley, Joel Schmutz, Julian B. Fischer, Dennis Marks

Spatial extent of seagrasses (Zostera marina and Ruppia maritima) along the central Pacific coast of Baja California, Mexico, 1999–2000

The seagrasses eelgrass (Zostera marina) and widgeongrass (Ruppia maritima) are prominent features of coastal lagoons along the Pacific coast of Baja California, Mexico, supporting a rich diversity of marine life. Yet little is known about their spatial distribution in this region. This is a concern because of declining trends in the abundance and distribution of seagrass in parts of northern Baja
Authors
David H. Ward, Alexandra Morton, Carl J. Markon, Kyle R. Hogrefe