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Five volcanic-hydrothermal systems in the central Aleutians Islands were sampled for water and gas geochemistry in 2015 to provide baseline data to help predict future volcanic unrest. Some areas had not been sampled in 20–30 years (Makushin volcano, Geyser Bight), and other areas had minimal to no prior sampling (Tana...

The National Petroleum Reserve in Alaska (NPR-A) encompasses more than 9.5 million hectares of federally managed land on the Arctic Coastal Plain of northern Alaska, where it supports a diversity of wildlife, including millions of migratory birds. Within the NPR-A, Teshekpuk Lake and the surrounding area provide important habitat for...

Continued Arctic warming and sea-ice loss will have important implications for the conservation of ringed seals, a highly ice-dependent species. A better understanding of their spatial ecology will help characterize emerging ecological trends and inform management decisions. We deployed satellite transmitters on ringed seals in the summers of 2011, 2014,...

Bald eagle (Haliaeetus leucocephalus) populations are classified by the Southwest Alaska Network (SWAN) of the National Park Service as a vital sign of biological integrity, largely because of their importance as an indicator species for environmental contaminants and human disturbance. Though Bald Eagles are plentiful in Alaska, it is still...

Large carnivores are negotiating increasingly developed landscapes, but little is known about how such behavioral plasticity influences their demographic rates and population trends. Some investigators have suggested that the ability of carnivores to behaviorally adapt to human development will enable their persistence, and yet, others have suggested that such landscapes...

Metamorphic rock fabrics such as foliations and lineations provide a rock record of numerous deformational characteristics in the Earth’s crust. When spatial information is combined with fabric data collected at points on geologic maps, the nature and consistency of metamorphic fabrics can be explored through structural domain analysis. This is...

The M 7.1 2018 Anchorage earthquake occurred in the bending part of the subducting North Pacific plate near the geometrical barrier formed by the underthrusting Yakutat terrane. We calculate the triggering potential related with stress redistribution from deformation sources including the M 9.2 1964 earthquake coseismic slip, postseismic deformation, slip from...

Muskoxen are a key species of Arctic ecosystems and are important for food security and socio-economic well-being of many Indigenous communities in the Arctic and Subarctic. Between 2009 and 2014, the bacterium Erysipelothrix rhusiopathiae was isolated for the first time in this species in association with multiple mortality events in Canada and Alaska, raising...

Near-field remote sensing of surface velocity and river discharge (discharge) were measured using coherent, continuous wave Doppler and pulsed radars. Traditional streamgaging requires sensors be deployed in the water column; however, near-field remote sensing has the potential to transform streamgaging operations through non-contact methods in the U.S. Geological Survey (USGS)...

The remote, inaccessible location of many rivers in Alaska creates a compelling need for remote sensing approaches to streamflow monitoring. Motivated by this objective, we evaluated the potential to infer flow velocities from optical image sequences acquired from a helicopter deployed above two large, sediment-laden rivers. Rather than artificial seeding,...

We reanalyzed mass balance records at Taku and Lemon Creek Glaciers to better understand the relative roles of hypsometry, local climate and dynamics as mass balance drivers. Over the 1946–2018 period, the cumulative mass balances diverged. Tidewater Taku Glacier advanced and gained mass at an average rate of +0.25±0.28 m...

The Steller’s eider (Polysticta stelleri) is a sea duck that breeds in Arctic tundra regions of Russia and Alaska. The Alaska-breeding population is listed as threatened under the U.S. Endangered Species Act because of a perceived contraction of their breeding range in North America. Understanding demographic rates of...

The recently released Landsat Analysis Ready Data (ARD) over the United States provides the opportunity to investigate landscape dynamics using dense time series observations at 30-m resolution. However, the dataset often contains data gaps (or missing data) because of cloud contamination or data acquisition strategy. We present a new algorithm...

Denali National Park (DENA) is home to iconic and breathtaking landscapes surrounding the tallest mountain range in North America, the Alaska Range. The park, which covers 6 million acres, is a major draw for tourism and recreation, making it an important economic engine for central Alaska. However, the geologic forces...

Birds often exhibit diagnostic traits that differ among individuals of the same species with regard to factors like sex, age, or breeding status. Shorebirds exhibit a wide diversity of colors, shapes, and sizes of their bills, and these traits are commonly used to determine the sex of individuals. In curlews...

We used Pinpoint GPS-Argos tags to track migration of Pacific Golden-Plovers Pluvialis fulva in 2017 and 2018 from Moorea Island, at the extreme southeastern edge of the species’ winter range. Of 20 tagged birds, 13 uploaded locations during all or part of their northward migration. The birds departed in mid-April traveling a...

Field surveys for aquatic organisms provide critical information that is important for robust resource management. However, such surveys are expensive and labor intensive, particularly in large, remote landscapes like those that characterize much of Alaska. Traditionally, characterizing aquatic biodiversity necessitated the physical capture and identification of individual organisms, which required...

We will investigate fish health factors that may be contributing to the failed recovery of Pacific herring populations in Prince William Sound. Field samples will provide infection and disease prevalence data from Prince William Sound and Sitka Sound that will inform the ASA model, serological data that will indicate the...

Recent work on cores and outcrops of the Middle-Upper Triassic Shublik Formation has facilitated surface to subsurface correlation of depositional sequences across the Alaska North Slope. Five transgressive-regressive depositional sequences have been defined within three large-scale stratigraphic units. Outcrop spectral gamma-ray (GR) profiles were used to correlate observed stacking patterns...

We present the first description of summer stream thermal regimes in Alaska using metrics that represent the magnitude, variability, frequency, duration, and timing of temperature events related to salmon life histories. We used cluster analysis to characterize thermal regimes present in the Matanuska-Susitna (Mat-Su) Basin based...

Alaska represents a globally important region for the ecology of avian-origin influenza A viruses (IAVs) given expansive wetlands in this region which serve as habitat for numerous hosts of IAVs that disperse among four continents during the annual cycle. Extensive sampling of wild birds for IAVs in Alaska since...

A method was developed and validated for the detection of colistin-resistant Escherichia coli containing mcr-1 in the feces of feral swine. Following optimization of an enrichment method using EC broth supplemented with colistin (1 µg/mL) and vancomycin (8 µg/mL), aliquots derived from 100 feral swine fecal samples were spiked with...

We report here on the first focused study of gas discharges and thermal spring waters at Okmok Volcano since the 2008 phreatomagmatic eruptions. Results include the first compositional gas data from Okmok with minimal air contamination and the first data on magmatic carbon in Okmok spring waters. Chemical and isotopic...

Erosion related to glacial activity produces enormous amounts of sediment. However, sediment mobilization in glacial systems is extremely complex. Sediment is derived from headwalls, slopes along the margins of glaciers, and basal erosion; however, the rates and relative contributions of each are unknown. To test and quantify conceptual models for...

In 2015, the mcr-1 gene was discovered in Escherichia coli in domestic swine in China that conferred resistance to colistin, an antibiotic of last resort used in treating multi-drug resistant bacterial infections in humans. Since then, mcr-1 was found in other human and animal populations, including wild gulls. Because gulls...