Research Wildlife Biologist
Alaska Science Center
Email:
afischbach@usgs.gov
Office Phone:
907-786-7145
Fax:
907-786-7150
ORCID:
0000-0002-6555-865X
Location
Glenn Olds Hall
4210 University Drive
Anchorage
, AK
99508-4626
US
Supervisor:
John M Pearce
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This data release has been SUPERSEDED. No data are provided here. The geospatial outlines and herd size estimates of Chukchi Sea autumn walrus haulouts, interpreted from Satellite imagery, have been combined into a single updated U.S. Geological Survey data release: https://doi.org/10.5066/P9CSM0KN 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 satellite imagery sources...
Tags: Alaska,
Animals/vertebrates,
Biota,
Cape Serdtse-Kamen,
Carnivores, All tags...
Chukchi Sea,
Chukotka,
Coastal ecosystems,
Environment,
Field inventory and monitoring,
Image collections,
Mammals,
Marine ecosystems,
Marine mammals,
Migratory species,
Odobenus rosmarus divergens,
Pacific Walrus,
Pinniped,
Point Lay,
Remote sensing,
Russia,
Satellite imagery,
Seals/sea lions/walruses,
Seasonal distribution,
USGS Science Data Catalog (SDC),
Walrus,
Wildlife, Fewer tags
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This data package contains 362 digital photos of a walrus haulout location at Cape Greig, on the Alaska Peninsula summer 2023 (2023-05-09 23:01:08 UTC through 2023-11-16 21:01:14 UTC). Photos were taken up to three times daily from a remotely operated camera located on a bluff above the haulout. The camera station was installed in the early spring 2023, prior to arrival of walruses at the site. Images are transferred via satellite link. Version History: First release: June 2023 Revised: January 2024 (ver. 2.0)
Categories: Data,
Data Release - Revised;
Tags: Alaska,
Animals/vertebrates,
Bering Sea,
Biota,
Cape Greig, All tags...
Carnivores,
Coastal ecosystems,
Environment,
Field inventory and monitoring,
Image collections,
Mammals,
Marine ecosystems,
Marine mammals,
Migratory species,
Odobenus rosmarus divergens,
Pacific Walrus,
Pinniped,
Remote photo imagery,
Remote sensing,
Seals/sea lions/walruses,
Seasonal distribution,
USGS Science Data Catalog (SDC),
Walrus,
Wildlife,
Wildlife Biology, Fewer tags
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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. Additional walrus satellite image-derived Chukchi Sea walrus haulout outlines are available in another USGS data release (Fischbach and Douglas 2022; https://doi.org/10.5066/P9CSM0KN)
Categories: Data;
Tags: Aerial surveys,
Age composition,
Alaska,
Animals/Vertebrates,
Biota, All tags...
Carnivores,
Chukchi Sea,
Coastal ecosystems,
Environment,
Field inventory and monitoring,
Mammals,
Marine ecosystems,
Marine mammals,
Migratory species,
Odobenus rosmarus divergens,
Pacific Walrus,
Point Lay,
Remote sensing,
Seals/sea lions/walruses,
Seasonal distribution,
USGS Science Data Catalog (SDC),
Walrus,
Wildlife,
Wildlife Biology, Fewer tags
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This dataset is derived from images from a variety of Earth observing satellite imagery sources collected at known walrus coastal haulouts in Alaska and Chukotka, Russia. Earth observing imagery sources used in this data release include (but are not limited to) optical imagery collections by: (1) the European Space Agency's Sentinel-2 mission, (2) the Plant Labs Planet Scope constellation, and (3) Maxar satellites, as well as synthetic aperture radar imagery collected by: (1) European Space Agency's Sentinel-1 mission, (2) the DLR (German Aerospace Agency) TerraSAR-X satellite, (3) the Umbra Space satellite constellation, (4) the Canadian Radarsat-2 satellite, (5) the Capella Space satellite constellation and (6)...
Categories: Data,
Data Release - Revised;
Tags: Alaska,
Animals/Vertebrates,
Biota,
Carnivores,
Chukchi Sea, All tags...
Chukotka,
Coastal ecosystems,
Environment,
Field inventory and monitoring,
Image collections,
Mammals,
Marine ecosystems,
Marine mammals,
Migratory species,
Odobenus rosmarus divergens,
Pacific Walrus,
Pinniped,
Remote sensing,
Russia,
Satellite imagery,
Seals/sea lions/walruses,
Seasonal distribution,
USGS Science Data Catalog (SDC),
Walrus,
Wildlife,
Wildlife Biology, Fewer tags
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The Pacific walrus (Odobenus rosmarus divergens) feeds on benthic invertebrates on the continental shelf of the Chukchi and Bering seas and rests on sea ice between foraging trips. With climate warming, ice-free periods in the Chukchi Sea have increased and are projected to increase in frequency and duration. We radio-tracked walruses to estimate areas of walrus foraging and occupancy in the Chukchi Sea during June–November of 2008–2011, years when sea ice was sparse over the continental shelf. The earlier and more extensive sea ice retreat in June–September and delayed freeze-up of sea ice in October and November, allowed walruses to arrive earlier, occupy slightly more northern areas, and stay later in the...
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