Population monitoring and modeling; applying population biology to problems of conservation and subsistence; managing records of population biology field work.
Professional Experience
2022 - Present Research Wildlife Biologist, USGS, Alaska Science Center, Anchorage, Alaska
2004 - 2022 Wildlife Biologist, USGS, Alaska Science Center, Anchorage, Alaska
2003 - 2004 Wildlife Biologist, U.S. Fish and Wildlife Service, Kodiak National Wildlife Refuge, Kodiak, Alaska
1999 - 2003 Wildlife Biologist, USGS, Alaska Biological Science Center, Anchorage, Alaska
1998 - 1999 Wildlife Biologist, Marine Mammals Management, U.S. Fish & Wildlife Service, Anchorage, Alaska
1997 - 1999 (summers) Volunteer Wildlife Biologist, Tongass Bat Habitat Project, U.S. Forest Service, Thorne Bay, Alaska
1995 - 1998 Biological Technician / Walrus Harvest Monitor, Marine Mammals Management, U.S. Fish & Wildlife Service, Anchorage, Alaska
1994 - 1995 Volunteer, Kenai National Wildlife Refuge, U.S. Fish & Wildlife Service, Soldotna, Alaska
Education and Certifications
M.A. 1994 University of Texas, Austin, TX Ecology
B.S. 1989 University of Wisconsin, Madison, WI Molecular Biology
Affiliations and Memberships*
Reviewer: BioScience, Arctic, Marine Mammal Science, Progress In Oceanography, Polar Biology
Contributor: R-sig-geo
Honors and Awards
1989-1990 Fulbright Scholar, Bayreuth, Germany
Science and Products
Walrus Research
Q&A: Estimates of Abundance for Pacific Walrus
Tracking Data for Pacific Walrus (Odobenus rosmarus divergens)
Pacific Walrus Coastal Haulout Occurrences Interpreted from Satellite Imagery, 2023
Pacific Walrus Coastal Haulout Images from Remote Cameras
Data Supporting Walrus Areas of Use in the Chukchi Sea During Sparse Sea Ice Cover
Walrus Haulout and In-water Activity Levels Relative to Vessel Interactions in the Chukchi Sea, 2012-2015
Pacific Walrus Coastal Haulout Occurrences Interpreted from Satellite Imagery
Tracking Data for Pacific Walrus (Odobenus rosmarus divergens)
Walrus Haulout Aerial Survey Data Near Point Lay Alaska, Autumn 2018 and 2019
Behavior of Pacific Walruses (Odobenus rosmarus divergens) Hauled Out on Sea Ice During UAS Overflights, Eastern Chukchi Sea, 2015
Walrus Haulout Outlines Apparent from Satellite Imagery Near Point Lay Alaska, Autumn 2018-2020
Walrus Haulout Outlines and Count Data Apparent from Aerial Survey Images Collected Near Point Lay Alaska, Autumn 2018 and 2019
Sex and Age Composition of Walrus Groups Hauled Out on Ice Floes in the Bering and Chukchi Seas, 2013-2015
Metabarcoding of Feces of Pacific Walruses and Autosomal DNA Sequence Data of Marine Invertebrates, 2012-2015, Alaska
Giardia and Cryptosporidium in resident wildlife species in Arctic Alaska
Exploring effects of vessels on walrus behaviors using telemetry, automatic identification system data and matching
Regional walrus abundance estimate in the United States Chukchi Sea in autumn
Evaluation of satellite imagery for monitoring Pacific walruses at a large coastal haulout
Variability of lipids and fatty acids in Pacific walrus blubber
DNA metabarcoding of feces to infer summer diet of Pacific walruses
Regional ocean models indicate changing limits to biological invasions in the Bering Sea
Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort and Chukchi Seas and nearby areas, 1910–2018
A multi-species synthesis of satellite telemetry data in the Pacific Arctic (1987–2015): Overlap of marine mammal distributions and core use areas
Forecasting consequences of changing sea ice availability for Pacific walruses
Assessing the risk of non-native marine species in the Bering Sea
Evaluation of a method using survey counts and tag data to estimate the number of Pacific walruses (Odobenus rosmarus divergens) using a coastal haulout in northwestern Alaska
R script for email delivery of sea ice imagery and charts to users with limited bandwidth
Science and Products
- Science
Walrus Research
The USGS Alaska Science Center conducts long-term research on the Pacific walrus to provide scientific information to Department of Interior management agencies and Alaska Native co-management partners. In addition, the USGS Pacific walrus research program collaborates with the U.S. Fish and Wildlife Service (USFWS) and the State of Alaska’s Department of Fish and Game and Alaska Native co...Q&A: Estimates of Abundance for Pacific Walrus
The Pacific walrus ranges across the Bering and Chukchi seas during the year. This wide geographic distribution makes it difficult to estimate Pacific walrus population abundance. However, recent technological advances in genetics and drone imagery have generated precise regional and range-wide abundance estimates.Tracking Data for Pacific Walrus (Odobenus rosmarus divergens)
Available here are tracking data of Pacific walrus, a marine mammal that ranges between the Alaska Peninsula, up through the Bering and Chukchi seas, and over to Russia. These data were collected from animals marked in the northern Bering and Chuckchi sea to understand seasonal movement patterns, use of coastal haulouts in northwestern Alaska, and determine estimates of abundance in autumn. - Data
Filter Total Items: 20
Pacific Walrus Coastal Haulout Occurrences Interpreted from Satellite Imagery, 2023
This data release contains maps, geospatial files, and a table of the satellite imagery types with the dates when they were collected and examined to interpret the presence of, and area occupied by, walruses at terrestrial haulouts. Estimates of the land area occupied by walruses are provided based on interpretation by experienced image reviewers. The images are from a variety of Earth observing sPacific Walrus Coastal Haulout Images from Remote Cameras
This data package contains digital photos of a walrus haulout location at Cape Greig, on the Alaska Peninsula summer 2023. Photos are taken up to three times daily from a remotely operated camera located on a bluff above the haulout. The camera was installed in the early spring 2023, prior to arrival of walruses at the site. Images are transferred via satellite link. A summary of image collectionData Supporting Walrus Areas of Use in the Chukchi Sea During Sparse Sea Ice Cover
The dataset consists of geospatial files depicting the estimated June-to-November distribution of walrus foraging and occupancy during a four year period of sparse sea ice cover above the Chukchi Sea continental shelf (2008-2011). The walrus distribution and utilization estimates are based on location data from satellite-linked radio-tracked walruses in the Chukchi Sea (2008-2011). Compared to preWalrus Haulout and In-water Activity Levels Relative to Vessel Interactions in the Chukchi Sea, 2012-2015
These data were used to evaluate effects of vessel exposure on Pacific walrus (Odobenus rosmarus divergens) behaviors. We obtained greater than 120,000 hours of location and behavior (foraging, in-water not foraging, hauled out) data from 218 satellite-tagged walruses and linked them to vessel locations from the marine Automated Information System. This yielded 206 vessel-exposed walrus telemetryPacific Walrus Coastal Haulout Occurrences Interpreted from Satellite Imagery
This data release contains maps, geospatial files, and a table of the satellite imagery types with the dates when they were collected and examined to interpret the presence of, and area occupied by, walruses at terrestrial haulouts. Estimates of the land area occupied by walruses are provided based on interpretation by experienced image reviewers. The images are from a variety of Earth observing sTracking Data for Pacific Walrus (Odobenus rosmarus divergens)
This metadata document describes the data contained in the "processedData" folder of this data package. This data package contains all data collected by the Argos System from 921 satellite transmitters attached to adult Pacific walruses in the Bering and Chukchi Seas, in U.S. and Russian waters, 1988-2019. The raw data were processed to accomplish two goals: flag implausible location estimates andWalrus Haulout Aerial Survey Data Near Point Lay Alaska, Autumn 2018 and 2019
This dataset consists of the complete set of aerial imagery and data from walrus haulouts collected by unoccupied aerial system (UAS) surveys near Pt. Lay, Alaska, during the autumns of 2018 and 2019. The data include: 1) georeferenced digital aerial imagery and flight logs from UAS surveys, and 2) orthoimages derived from the aerial imagery and flight logs by standardized structure from motion alBehavior of Pacific Walruses (Odobenus rosmarus divergens) Hauled Out on Sea Ice During UAS Overflights, Eastern Chukchi Sea, 2015
This dataset is comprised of three tables showing the reaction of walruses hauled out on sea ice of the Chukchi Sea to overflights by rotary wing Unoccupied Aircraft Systems (UAS). Data include behavior of walruses before, during, and after overflights, and environmental conditions during flights.Walrus Haulout Outlines Apparent from Satellite Imagery Near Point Lay Alaska, Autumn 2018-2020
These data are in three folders of Keyhole Markup Language (KML) geospatial polygons representing the outlines of walrus herds apparent in satellite imagery. Each KML file contains one or more geospatial polygons of walrus herd outlines created by one observer who visually interpreted the images. The attribute values from all KML files are collected in a CSV table included with this data package.Walrus Haulout Outlines and Count Data Apparent from Aerial Survey Images Collected Near Point Lay Alaska, Autumn 2018 and 2019
This dataset provides walrus haulout group outlines, systematic grids cast over the outlines, and digitized points at the centroids of the individual walruses identified inside a randomly selected subset of grid cells. These data are based on visual interpretation of unpublished imagery from 26 aerial surveys by an Unoccupied Aerial System (UAS) operated by the U.S. Geological Survey, Alaska ScienSex and Age Composition of Walrus Groups Hauled Out on Ice Floes in the Bering and Chukchi Seas, 2013-2015
These data are in one table with age and sex composition counts of groups of walruses on ice floes in the northern Bering and Chukchi Seas. Counts were collected by visual observations from boats.Metabarcoding of Feces of Pacific Walruses and Autosomal DNA Sequence Data of Marine Invertebrates, 2012-2015, Alaska
This data set describes nucleotide sequence data derived from 18S ribosomal DNA amplified in two fragments. A total of 87 feces from Pacific walrus and 57 marine invertebrates were examined for this study. Samples were collected from the Bering Sea and Chukchi Sea, Alaska. Samples used in the study originated from feces or muscle samples collected in the field from ice floes or benthic van Veen gr - Multimedia
- Publications
Filter Total Items: 38
Giardia and Cryptosporidium in resident wildlife species in Arctic Alaska
Giardia and Cryptosporidium are zoonotic protozoan parasites that can infect humans and other taxa, including wildlife, often causing gastrointestinal illness. Both have been identified as One Health priorities in the Arctic, where climate change is expected to influence the distribution of many wildlife and zoonotic diseases, but little is known about their prevalence in local wildlife. To help fAuthorsCaroline R. Van Hemert, Lora Ballweber, David R. Sinnett, Todd C. Atwood, Anthony S. Fischbach, David Gustine, Kristy PabiloniaExploring effects of vessels on walrus behaviors using telemetry, automatic identification system data and matching
Arctic marine mammals have had little exposure to vessel traffic and potential associated disturbance, but sea ice loss has increased accessibility of Arctic waters to vessels. Vessel disturbance could influence marine mammal population dynamics by altering behavioral activity budgets that affect energy balance, which in turn can affect birth and death rates. As an initial step in studying these lAuthorsRebecca L. Taylor, Chadwick V. Jay, William S. Beatty, Anthony S. Fischbach, Lori T. Quakenbush, Justin A. CrawfordRegional walrus abundance estimate in the United States Chukchi Sea in autumn
Human activities (e.g., shipping, tourism, oil, gas development) have increased in the Chukchi Sea because of declining sea ice. The declining sea ice itself and these activities may affect Pacific walrus (Odobenus rosmarus divergens) abundance; however, previous walrus abundance estimates have been notably imprecise. When sea ice is absent from the eastern Chukchi Sea, walruses in waters of the UAuthorsAnthony S. Fischbach, Rebecca L. Taylor, Chadwick V. JayEvaluation of satellite imagery for monitoring Pacific walruses at a large coastal haulout
Pacific walruses (Odobenus rosmarus divergens) are using coastal haulouts in the Chukchi Sea more often and in larger numbers to rest between foraging bouts in late summer and autumn in recent years, because climate warming has reduced availability of sea ice that historically had provided resting platforms near their preferred benthic feeding grounds. With greater numbers of walruses hauling outAuthorsAnthony S. Fischbach, David C. DouglasVariability of lipids and fatty acids in Pacific walrus blubber
The variability of lipid content and fatty acid (FA) composition across blubber depth and body sites are important considerations for condition and diet studies of marine mammals. We investigated lipid and FA variability among inner and outer blubber layers, three body sites, four study years, and lactation status of adult female Pacific walruses (Odobenus rosmarus divergens) using blubber samplesAuthorsChadwick V. Jay, Sara J. Iverson, Anthony S. FischbachDNA metabarcoding of feces to infer summer diet of Pacific walruses
Environmental conditions in the Chukchi Sea are changing rapidly and may alter the abundance and distribution of marine species and their benthic prey. We used a metabarcoding approach to identify potentially important prey taxa from Pacific walrus (Odobenus rosmarus divergens) fecal samples (n = 87). Bivalvia was the most dominant class of prey (66% of all normalized counts) and occurred in 98% oAuthorsSarah A. Sonsthagen, Chadwick V. Jay, Robert S. Cornman, Anthony S. Fischbach, Jacqueline M. Grebmeier, Sandra L. TalbotRegional ocean models indicate changing limits to biological invasions in the Bering Sea
Minimal vessel traffic and cold water temperatures are believed to limit non-indigenous species (NIS) in high-latitude ecosystems. We evaluated whether suitable conditions exist in the Bering Sea for the introduction, survival, and reproduction of NIS. We compiled temperature and salinity thresholds of known NIS and compared these to ocean conditions projected during two study periods: current (20AuthorsAmanda Droghini, Anthony S. Fischbach, Jordan Watson, Jesika ReimerCatalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort and Chukchi Seas and nearby areas, 1910–2018
This report presents data on the approximate locations and methods of discovery of 530 polar bear (Ursus maritimus) maternal dens observed in the Beaufort and Chukchi Seas and neighboring areas from 1910 to 2018, and archived partly by the U.S. Geological Survey, Alaska Science Center, and partly by the U.S. Fish and Wildlife Service, Marine Mammals Management, in Anchorage, Alaska. A descriptionAuthorsGeorge M. Durner, Steven C. Amstrup, Todd C. Atwood, David C. Douglas, Anthony S. Fischbach, Jay W. Olson, Karyn D. Rode, Ryan H. WilsonA multi-species synthesis of satellite telemetry data in the Pacific Arctic (1987–2015): Overlap of marine mammal distributions and core use areas
We collated available satellite telemetry data for six species of ice-associated marine mammals in the Pacific Arctic: ringed seals (Pusa hispida; n = 118), bearded seals(Erignathus barbatus, n = 51), spotted seals (Phoca largha, n = 72), Pacific walruses (Odobenus rosmarus divergens, n = 389); bowhead whales (Balaena mysticetus, n = 46), and five Arctic and sub-arctic stocks of beluga whales (DelAuthorsJohn J. Citta, Lloyd F. Lowry, Lori T. Quakenbush, Brendan P. Kelly, Anthony S. Fischbach, Josh M. London, Chadwick V. Jay, Kathryn J. Frost, Gregory O'Corry Crowe, Justin A. Crawford, Peter L. Boveng, Michael Cameron, Andrew L. Von Duyke, Mark Nelson, Lois A. Harwood, Pierre Richard, Robert Suydam, Mads Peter Heide-Jørgensen, Roderick C. Hobbs, Dennis I. Litovka, Marianne Marcoux, Alex Whiting, Amy S. Kennedy, John C. George, Jack Orr, Tom GrayForecasting consequences of changing sea ice availability for Pacific walruses
The accelerating rate of anthropogenic alteration and disturbance of environments has increased the need for forecasting effects of environmental change on fish and wildlife populations. Models linking projections of environmental change with behavioral responses and bioenergetic effects can provide a basis for these forecasts. There is particular interest in forecasting effects of projected reducAuthorsMark S. Udevitz, Chadwick V. Jay, Rebecca L. Taylor, Anthony S. Fischbach, William S. Beatty, Shawn R. NorenAssessing the risk of non-native marine species in the Bering Sea
Invasive species are one of the leading global conservation concerns, which can have strong, negative impacts on ecosystems, vulnerable species, and valuable natural resources. Arctic regions have experienced a relatively low number of biological introductions to date. Their geographical remoteness, cold waters, and presence of sea ice present challenging conditions for both non-native organisms aAuthorsJesika Reimer, Amanda Droghini, Anthony S. Fischbach, Jordan Watson, Bonnie Bernard, Aaron PoeEvaluation of a method using survey counts and tag data to estimate the number of Pacific walruses (Odobenus rosmarus divergens) using a coastal haulout in northwestern Alaska
Increased periods of sparse sea ice over the continental shelf of the Chukchi Sea in late summer have reduced offshore haulout habitat for Pacific walruses (Odobenus rosmarus divergens) and increased opportunities for human activities in the region. Knowing how many walruses could be affected by human activities would be useful to conservation decisions. Currently, there are no adequate estimatesAuthorsBrian Battaile, Chadwick V. Jay, Mark S. Udevitz, Anthony S. Fischbach - Software
R script for email delivery of sea ice imagery and charts to users with limited bandwidth
This software package represents an effort to enable access of sea ice charts and imagery in support of daily logistics planning where internet bandwidth and geoprocessing abilities are limited. The script acquires, processes and delivers these data in a format that may be manipulated by openly available virtual globe software, be visualized by software commonly installed on all smart phones and c - News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government