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With warmer springs, herbivores migrating to Arctic breeding grounds may experience phenological mismatches between their energy demands and the availability of high quality forage. However, the timing of high quality forage relative to the timing of grazing is often unknown. In coastal western Alaska, approximately one million migratory geese arrive...

Arctic permafrost stores vast amounts of methane (CH4) in subsurface reservoirs. Thawing permafrost creates areas for this potent greenhouse gas to be released to the atmosphere. Identifying ‘hot spots’ of methane flux on a local scale has been limited by the spatial scales of traditional ground-based or satellite-based methane-sampling methods....

Given their popularity with researchers and public alike, together with their welldocumented importance in aquatic and terrestrial ecosystems, fundamental and applied research on swans continues to develop in the 21st century. The 6th International Swan Symposium (6th ISS), was held at the Estonian University of Life Sciences in Tartu, Estonia,...

We present here the results of multi-proxy analyses (sediment geochemistry, diatoms, and pollen) from sediment cores collected at four lakes in the middle Susitna Valley, Alaska. These lakes form a transect from the tundra to the boreal forest. The retrieved cores span from ~12,000 cal yr BP to the present,...

Peat cores are valuable archives of past environmental change because they accumulate plant organic matter over millennia. While studies have primarily focused on physical, ecological, and some biogeochemical proxies, cores from peatlands have increasingly been used to interpret hydroclimatic change using stable isotope analyses of cellulose preserved in plant remains....

Wild birds in the order Anseriformes are important reservoirs for influenza A viruses (IAV); however, IAV prevalence and subtype diversity may vary by season, even at the same location. To better understand the ecology of IAV during waterfowl migration through the Gulf Coast of the United States (Louisiana and Texas),...

Contemporary climate change in Alaska has resulted in amplified rates of press and pulse disturbances that drive ecosystem change with significant consequences for socio‐environmental systems. Despite the vulnerability of Arctic and boreal landscapes to change, little has been done to characterize landscape change and associated drivers across northern high‐latitude ecosystems....

Snow avalanches cause many fatalities every year and damage local economies worldwide. The present-day climate change affects the snowpack and, thus, the properties and frequency of snow avalanches. Reconstructing snow avalanche records can help us understand past variations in avalanche frequency and their relationship to climate change. Previous avalanche records...

Annual survival and recruitment in black brant (Branta bernicla nigricans) have declined since the 1990s, yet aerial surveys of the global population have been stable or even increasing over the past decade. We used a combination of a Lincoln estimator based on harvest information and band recoveries, and marked‐unmarked ratios...

The study of avian movement has detailed a spectrum of strategies for the timing and use of sites throughout the annual cycle, from near randomness to complete consistency. New tracking devices now permit the repeated tracking of individual animals throughout the annual cycle, detailing previously unappreciated levels of variation within...

On average, band recovery rates of adult black brant (Branta bernicla nigricans) more than doubled between the 2000s and 2010s. However, the spatial distribution of band recoveries of black brant has not been reported. Our objective was to describe the spatial distribution of band recoveries of black brant since 1990....

Tephrochronology is used to correlate and reconstruct geographically disparate sedimentary records of changing environment, climate, and landscape throughout geologic time. Single tephra layers represent isochronous markers across broad regions, thus accurate and precise radiometric constraints on the timing of eruption are critical to their...

Rates of northern Alaska Range thrust system deformation are poorly constrained. Shortening at the system's west end is focused on the Kantishna Hills anticline. Where the McKinley River cuts across the anticline, the landscape records both Late Pleistocene deformation and climatic change. New optically stimulated luminescence and cosmogenic 10Be depth profile...

Sea stars are ecologically important in rocky intertidal habitats where they can play an apex predator role, completely restructuring communities. The recent sea star die-off throughout the eastern Pacific, known as Sea Star Wasting Disease, has prompted a need to understand spatial and temporal patterns of sea star assemblages and...

Many marine organisms show significant levels of genetic heterogeneity on local spatial scales despite exhibiting limited genetic structure at large geographic scales which can be produced through a variety of mechanisms. The Arctic cod (Boreogadus saida) is a circumpolar species and is a vital species in Arctic food webs. To...

High-latitude environments store nearly half of the planet’s below-ground organic carbon (OC), mostly in perennially frozen permafrost soils. Climatic changes drive increased export of terrestrial OC into many aquatic networks, yet the role that circumpolar lakes play in mineralizing this carbon is unclear. Here we directly evaluate ecosystem-scale OC cycling...

This document defines a U.S. Geological Survey (USGS) digital topographic map. This map product series, named “US Topo,” is modeled on the now historical USGS 7.5-minute (1:24,000 scale) topographic map series produced and printed by the USGS from 1947 to 2006. US Topo maps have the...

Climate change is altering the distribution of some wildlife species while warming temperatures are facilitating the northward expansion of pathogens, potentially increasing disease risk. Melting of Arctic sea ice is causing polar bears (Ursus maritimus) of the Southern Beaufort Sea (SBS) to increasingly spend summer on land, where they may...

Estimation of trade-offs between current reproduction and future survival and fecundity of long-lived vertebrates is essential to understanding factors that shape optimal reproductive investment. Black brant geese (Branta bernicla nigricans) fledge more goslings, on average, when their broods are experimentally enlarged to be greater than the most common clutch size...

Dall's porpoise, Phocoenoides dalli, are a conspicuous predator in the Prince William Sound ecosystem, yet there has been little effort directed towards monitoring this species since the 1980s, prior to the Exxon Valdez oil spill. We used vessel-based surveys to examine the seasonal distribution of Dall's porpoise in the waters...

The potential for a major earthquake in the Shumagin seismic gap, and the tsunami it could generate, was reported in 1971. However, while potentially tsunamigenic splay faults in the adjacent Unimak and Semidi earthquake segments are known, such features along the Shumagin segment were undocumented until recently. To investigate margin...

The 2013 Craig, Alaska MW 7.5 earthquake ruptured along ∼150 km of the Queen Charlotte Fault (QCF), a right-lateral strike-slip plate boundary fault separating the Pacific and North American plates. Regional shear wave analyses suggest that the Craig earthquake rupturepropagated in the northward direction faster than the S-wave (supershear). Theoretical studies suggest that a bimaterial interface, such as that along the QCF, which...

The evolutionary consequences of natural introgression provide a rare opportunity to retrospectively evaluate how the introduction of exotics or genetic rescue efforts may impact endemic faunas. Phylogeographic structure among mainland, endemic insular, and introduced North American marten (Martes americana and M. caurina) populations have been shaped by a...

Arctic lowlands are characterized by large numbers of small waterbodies, which are known to affect surface energy budgets and the global carbon cycle. Statistical analysis of their size distributions has been hindered by the shortage of observations at sufficiently high spatial resolutions. This situation has now changed with the high-resolution...

Lakes in boreal lowlands cycle carbon and supply an important source of freshwater for wildlife and migratory waterfowl. The abundance and distribution of these lakes are supported, in part, by permafrost distribution, which is subject to change. Relationships between permafrost thaw and lake dynamics remain poorly known in most boreal...