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Page 14, results 326 - 350

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Publication Extents

Not all publications have extents, not all extents are completely accurate
A test of the green wave hypothesis in omnivorous brown bears across North America
Nathaniel R. Bowersock, L. M. Ciarniello, William W. Deacy, D. C. Heard, Kyle Joly, Clayton T. Lamb, William B. Leacock, Bruce Mclellan, Garth Mowat, Mathew S Sorum, Frank T. van Manen, Jerod A. Merkle
2023, Ecography (2023)
Herbivorous animals tend to seek out plants at intermediate phenological states to improve energy intake while minimizing consumption of fibrous material. In some ecosystems, the timing of green-up is heterogeneous and propagates across space in a wave-like pattern, known as the green wave. Tracking the green wave allows individuals to...
Ocean current patterns drive the worldwide colonization of eelgrass (Zostera marina)
Lei Yu, Marina Khachaturyan, Michael Matschiner, Adam Healey, Diane Bauer, Brenda Cameron, Mathieu Cusson, J. Emmett Duffy, F. Joel Fodrie, Diana Gill, Jane Grimwood, Masakazu Hori, Kevin Hovel, A. Randall Hughes, Marlene Jahnke, J. Jenkins, K. Keymanesh, C. Kruschel, S. Mamidi, Damian M. Menning, P. Moksnes, M. Nakaoka, C. Pennacchio, K. Reiss, F. Rossi, J. Ruesink, S. Schultz, S. Talbott, R. Unsworth, David H. Ward, T. Dagan, J. Schmutz, J. A. Eisen, J. Stachowicz, Y. Van de Peer, J. L. Olsen, T. B. H. Reusch
2023, Nature Plants (9) 1207-1220
Currents are unique drivers of oceanic phylogeography and thus determine the distribution of marine coastal species, along with past glaciations and sea-level changes. Here we reconstruct the worldwide colonization history of eelgrass (Zostera marina L.), the most widely distributed marine flowering plant or seagrass from its origin in the Northwest Pacific,...
Comparing sediment microbial communities of Arctic beaver ponds to tundra lakes and streams
Kelly Shannon, Natasha R. Christman, Byron C. Crump, Michael P. Carey, Joshua C. Koch, Laura L. Lapham, Jonathan A. O’Donnell, Brett A. Poulin, Ken D. Tape, Jason A. Clark, Frederick S. Colwell
2023, Journal of Geophysical Research: Biogeosciences (128)
In recent decades the habitat of North American beaver (Castor canadensis) has expanded from boreal forests into Arctic tundra ecosystems. Beaver ponds in Arctic watersheds are known to alter stream biogeochemistry, which is likely coupled with changes in the activity and composition of microbial communities inhabiting beaver...
Sexual dimorphism in endangered Jemez Mountains Salamanders (Plethodon neomexicanus)
Nancy E. Karraker, Rachel A. Loehman, Samantha Cordova
2023, Journal of Herpetology (57) 204-210
Sex ratio is a key demographic characteristic indicative of the condition of populations. Despite over 70 yr of study, researchers have not fully evaluated morphological characteristics that differentiate sex in Jemez Mountains Salamanders (Plethodon neomexicanus; federally endangered). Populations of this endemic salamander, which are...
Forecasts of polar bear (Ursus maritimus) land use in the southern Beaufort and Chukchi Seas, 2040–65
Karyn D. Rode, David C. Douglas, Todd C. Atwood, Ryan R. Wilson
2023, Open-File Report 2023-1048
This report provides analysis to extend the 2040 forecasts of polar bear (Ursus maritimus) land use for the southern Beaufort and Chukchi Sea populations presented in a recent publication (Rode and others, 2022) through the year 2065. To inform long-term polar bear management considerations, we provide point-estimate forecasts and 95-percent...
Apparent discrepancies in the review “Avian host range of Chlamydophila spp. based on isolation, antigen detection and serology” by Kaleta, E.F. & Taday, E.M.A. (2003), Avian Pathology, 32, 435–462
J. Christian Franson
2023, Avian Pathology (52) 283-284
Citing published reports and their own diagnostic data, Kaleta and Taday (Citation2003) (https://doi.org/10.1080/03079450310001593613) reported that 469 domestic and free-living bird species were determined to be chlamydia-positive, based on isolation of the organism and antigen detection or on serological detection of circulating antibodies. However, I was unable to...
Changes in abiotic drivers of green sea urchin demographics following the loss of a keystone predator
Ben P. Weitzman, B. Konar, M. S. Edwards, D. B. Rasher, Michael C. Kenner, M. T. Tinker, J. A. Estes
2023, Journal of Marine Sciences (2023)
Sea urchin population demographics can respond to changes in keystone species abundances, with the magnitude of these responses varying depending on environmental influences. In this study, sea urchin populations were surveyed across 15 Aleutian archipelago islands over a 30-year period to understand how patterns of sea urchin demography (density, biomass,...
Structure of breeding calls in three closely related bird species (Calidris Merrem, 1804; Scolopacidae)
Edward H. Miller, Pavel S. Tomkovich, Vladimir Yu. Arkhipov, Colleen M. Handel
2023, Canadian Journal of Zoology (101) 869-885
We studied calls of three sandpiper species to document species’ similarities and differences. We hypothesized that functionally different calls would differ in degree of divergence. We studied two nuptial calls (complex “Song” and rhythmically repeated aerial call, RRC) of males, and a general-purpose call (“alarm” trill, AT)...
Nearshore ecosystems in the Gulf of Alaska
Heather A. Coletti, Daniel Esler, Brenda Ballachey, Jim Bodkin, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Brian H. Robinson, Sarah Beth Traiger, Katrin Iken, Brenda Konar, Tom Dean, Mandy Lindeberg, Ben Weitzman
2023, Report
Nearshore ecosystem monitoring in western Prince William Sound, Kenai Fjords National Park, Kachemak Bay, and Katmai National Park and Preserve has been conducted as a single Nearshore Component of the Gulf Watch Alaska program over the past five years (2017-2021). This program builds on the previous five years and continues,...
A 1300-year microfaunal record from the Beaufort Sea shelf indicates exceptional climate-related environmental changes over the last two centuries
Jade Falardeau, Anne de Vernal, Marit-Solveig Seidenkrantz, Michael Fritz, Thomas M. Cronin, Laura Gemery, Andre Rochon, Vladislav Carnero-Bravo, Claude Hillaire-Marcel, Christof Pearce, Philippe Archambault
2023, Palaeogeography, Palaeoclimatology, Palaeoecology (625)
The environments of Arctic Ocean nearshore areas experience high intra- and inter-annual variability, making it difficult to evaluate the impact of anthropogenic warming. However, a sediment record from the southern Canadian Beaufort Sea allowed us to reconstruct the impacts of climate and environmental changes over the last 1300 years along the northern Yukon...
Age-0 sablefish size and growth indices from seabird diets at Middleton Island, Gulf of Alaska
Mayumi L. Arimitsu, Scott A. Hatch
2023, Open-File Report 2023-1049
Sablefish (Anoplopoma fimbria) is a commercially valuable groundfish species in Alaska, with the population assessed annually by the National Oceanic and Atmospheric Administration Alaska Fisheries Science Center. Sablefish recruit into the commercially fished population at 2 years old and are poorly sampled by most surveys before that age. However, information...
A body composition model with multiple storage compartments for polar bears (Ursus maritimus)
Stephanie R. Penk, Pranav Sadana, Louise C. Archer, Anthony M. Pagano, Marc R. L. Cattet, Nicholas J. Lunn, Gregory W. Thiemann, Peter K. Molnar
2023, Article
Climate warming is rapidly altering Arctic ecosystems. Polar bears (Ursus maritimus) need sea ice as a platform from which to hunt seals, but increased sea-ice loss is lengthening periods when bears are without access to primary hunting habitat. During periods of food scarcity, survival depends on the energy that a...
A hierarchical modelling framework for estimating individual- and population-level reproductive success from movement data
Joseph Michael Eisaguirre, Perry J. Williams, Julia C. Brockman, Stephen B. Lewis, Christopher P. Barger, Greg A. Breed, Travis L. Booms
2023, Methods in Ecology and Evolution (14) 2110-2122
Rapidly advancing animal telemetry technologies paired with new statistical models can provide insight into the behaviour of otherwise unobservable free-living animals. Changes in behaviour apparent from pairing telemetry with statistical models often occur as animals undertake key life-history activities, such as reproduction. For many species that are secretive or...
Geographic isolation reduces genetic diversity of a wide-ranging terrestrial vertebrate, Canis lupus
S.A. Frevol, D. R. MacNulty, M. C. Anderson, H. D. Cluff, L. David Mech, M. Musiani
2023, Ecosphere (14)
Genetic diversity is theorized to decrease in populations closer to a species' range edge, where habitat may be suboptimal. Generalist species capable of long-range dispersal may maintain sufficient gene flow to counteract this, though the presence of significant barriers to dispersal (e.g., large water...
Volcanic and tectonic sources of seismicity near the Tanaga Volcanic Cluster, Alaska
Kevin Lally, Jackie Caplan-Auerbach, John Power
2023, Geochemistry, Geophysics, Geosystems (24)
Tanaga Island in the Central Aleutian Islands includes four stratovolcanoes: Sajaka, Tanaga, and East Tanaga in the northwest, and Takawangha in the central part of the island. Of these volcanoes, only Tanaga has a confirmed record of historical eruptive activity. We use double-difference methods to relocate Tanaga...
Quantification of wetland vegetation communities features with airborne AVIRIS-NG, UAVSAR, and UAV LiDAR data in Peace-Athabasca Delta
Chao Wang, Tamlin M. Pavelsky, Ethan D. Kyzivat, Fenix Garcia-Tigreros, Erika Podest, Fangfang Yao, Xiao Yang, Shuai Zhang, Conghe Song, Theodore Langhorst, Wayana Dolan, Martin R. Kurek, Merritt E. Harlan, Laurence C. Smith, David Butman, Robert G.M. Spencer, Colin J. Gleason, Kimberly Wickland, Robert G. Striegl, Daniel L. Peters
2023, Remote Sensing of Environment (294)
Arctic-boreal wetlands, important ecosystems for biodiversity and ecological services, are experiencing hydrological changes including permafrost thaw, earlier snowmelt, and increased wildfire susceptibility. These changes are affecting wetland productivity, species diversity, and biogeochemical cycles. However, given the diverse forms and structures of wetland vegetation...
Modeling, mapping, and measuring the risk of freshwater invasive species across Alaska
Marcus Geist, Catherine S. Jarnevich, Anjanette Steer, Jeanne Osnas, Michael P. Carey, Aaron C. Martin, Tammy Davis, Rachel Kelty
2023, Report
Freshwater ecosystems of the Alaskan Arctic and Subarctic provide resources that are culturally, ecologically, and economically invaluable. Presently, these regions are relatively free of the impacts from invasive species compared to southern latitudes. To date, there have been relatively few verified introductions of aquatic invasive species (AIS) to freshwater ecosystems...
Geochronology and mapping constraints on the time-space evolution of the igneous and hydrothermal systems in the Taurus Cu-Mo district, eastern Alaska
Douglas C. Kreiner, Christopher S. Holm-Denoma, Laura Pianowski, Zachary Flood, David J. Stevenson, Garth E. Graham, Jorge A. Vazquez, Robert A Creaser
2023, Economic Geology (118) 745-778
The Taurus porphyry Cu-Mo district contains four mineralized porphyry centers in the eastern interior of Alaska. All four centers were emplaced during a magmatic episode that spanned from ca. 72 to 67 Ma, with seven distinct igneous suites. Each igneous suite resulted in hydrothermal alteration and mineralization, with younger pulses...
Climate change and coastal wetland salinization: Physiological and ecological consequences for Arctic waterfowl
Tuula E. Hollmen, Paul L. Flint, Sadie Ulman, H.M. Wilson, Courtney Amundson, Erik E. Osnas
2023, Functional Ecology (37) 1884-1896
Coastal wetland salinization related to warming climate has the potential to impact ecological systems globally. In Alaska, the Yukon-Kuskokwim Delta (YKD) supports large concentrations of breeding water birds and is an ecologically important area for conservation of migratory bird biodiversity. On the YKD, the majority of waterfowl nest in...
High voltage: The molecular properties of redox-active dissolved organic matter in northern high-latitude lakes
Martin R. Kurek, Fenix Garcia-Tigreros, Natalie A. Nichols, Gregory K. Druschel, Kimberly Wickland, Mark M. Dornblaser, Robert G. Striegl, Sydney F. Niles, Amy M. McKenna, Pieter J.K Aukes, Ethan D. Kyzivat, Chao Wang, Laurence C. Smith, Sherry L. Schiff, David Butman, Robert G.M. Spencer
2023, Environmental Science & Technology (57) 8617-8627
Redox-active functional groups in dissolved organic matter (DOM) are crucial for microbial electron transfer and methane emissions. However, the extent of aquatic DOM redox properties across northern high-latitude lakes and their relationships with DOM composition have not been thoroughly described. We quantified...
Gene expression and wildlife health: Varied interpretations based on perspective
Lizabeth Bowen, Julie L. Yee, James L. Bodkin, Shannon C. Waters-Dynes, Michael J. Murray, Heather Coletti, Brenda E. Ballachey, Daniel Monson, A. Keith Miles
2023, Frontiers in Ecology and Evolution (11)
We evaluated wildlife population health from the perspective of statistical means vs. variances. We outlined the choices necessary to provide the framework for our study. These consisted of spatial and temporal boundaries (e.g., choice of sentinel species, populations, time frame), measurement techniques (molecular to population level), and appropriate statistical analyses....
Barrier island reconfiguration leads to rapid erosion and relocation of a rural Alaska community
Richard M. Buzard, Nicole E.M. Kinsman, Christopher V. Maio, Li H. Erikson, Benjamin M. Jones, Scott K. Anderson, Roberta Glenn, Jacquelyn R. Overbeck
2023, Journal of Coastal Research (39) 625-642
Coastal erosion is one of the foremost hazards that circumpolar communities face. Climate change and warming temperatures are anticipated to accelerate coastal change, increasing risk to coastal communities. Most erosion hazard studies for Alaska communities only consider linear erosion and do not anticipate coastal morphologic changes. This study showcases the...
Environmental antimicrobial resistance gene detection from wild bird habitats using two methods: A commercially available culture-independent qPCR assay and culture of indicator bacteria followed by whole-genome sequencing
Christina Ahlstrom, Laura Celeste Scott, Hanna Woksepp, Jonas Bonnedahl, Andrew M. Ramey
2023, Journal of Global Antimicrobial Resistance (33) 186-193
ObjectivesA variety of methods have been developed to detect antimicrobial resistance (AMR) in different environments to better understand the evolution and dissemination of this public health threat. Comparisons of results generated using different AMR detection methods, such as quantitative PCR (qPCR) and whole-genome sequencing...
Exchange of carbapenem-resistant Escherichia coli Sequence Type 38 intercontinentally and among wild bird, human, and environmental niches
Christina Ahlstrom, Hanna Woksepp, Linus Sandegren, Andrew M. Ramey, Jonas Bonnedahl
2023, Applied and Environmental Microbiology (89)
Carbapenem-resistant Enterobacteriaceae (CRE) are a global threat to human health and are increasingly being isolated from nonclinical settings. OXA-48-producing Escherichia coli sequence type 38 (ST38) is the most frequently reported CRE type in wild birds and has been detected in gulls or storks in North America, Europe, Asia, and Africa. The epidemiology...
2019 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory
Tim R. Orr, Cheryl E. Cameron, Hannah R. Dietterich, James P. Dixon, Max L. Enders, Ronni Grapenthin, Alexandra M. Iezzi, Matthew W. Loewen, John A. Power, Cheryl Searcy, Gabrielle Tepp, Liam Toney, Christopher F. Waythomas, Aaron G. Wech
2023, Scientific Investigations Report 2023-5039
The Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at 17 volcanic centers in Alaska in 2019. The most notable volcanic activity was an eruption of Shishaldin Volcano, featuring eruptive activity that produced lava flows, lahars, and ash. Weak explosive activity...