Alaska Science Center


Response of Pacific Walrus Populations to a Rapidly Diminishing Sea Ice Environment

A long term research program on Pacific walruses to inform local, state, national and international policy makers regarding conservation of the species and its habitat. The goal of our current research efforts is to refine and enhance models to project the future status of the Pacific walrus in the rapidly changing Arctic environment.

Abstract


Sea ice decline and its impact on Pacific walruses are of great concern. Female walruses use sea ice to rest and nurse their young in the Bering and Chukchi Seas. They rely on the close proximity of sea ice to the continental shelf where their benthic prey is abundant and accessible to shallow foraging. Sea ice is less extensive and thinner in the Bering Sea, retreating more quickly in late spring, and is less extensive over the shelf in the Chukchi Sea in summer and early fall, than in previous years. This may alter walrus foraging distribution and behavior in the Bering Sea and has resulted in more rapid northward migration of walruses and decreased sea ice habitat within their summer foraging range. Walruses have become less accessible to Alaska Native subsistence hunting, and anecdotal information suggests that female walruses and calves are responding to decreased sea ice in summer by increasing their use of land haul-outs in Russia, possibly leading to more costly foraging energetics and decreased calf survival. In addition, oil and gas exploration in northern lease sale planning areas has prompted requests for more information on walrus migration routes and foraging areas in the Chukchi Sea, which are currently not well documented. This information is important to oil and gas industry to help mitigate potential impacts to walruses from offshore exploration and development activities; U.S. Bureau of Ocean Energy Management and Fish and Wildlife Service for oil and gas lease sales, MMPA authorizations, NEPA analyses, and as documentation in the approval of exploration and development plans; and to coastal Native communities that rely on sufficient nearshore access to walruses for subsistence. USGS is responding to these information needs by initiating new radio-tagging studies in the Bering and Chukchi Seas to better understand changes in walrus distributions and foraging behaviors relative to sea ice conditions. Other studies will be initiated to gain insights into likely population responses to altered walrus distributions and foraging strategies, and an improved understanding of ice dynamics in the Bering and Chukchi Seas relevant to the lives of walruses.
Products
Title Type
Pacific Walrus Coastal Haulout Images from Carcass SurveysData
Pacific Walrus Coastal Haulout Images from Remote Camera StationsData
Walrus Haulout and In-water Activity Levels Relative to Vessel Interactions in the Chukchi Sea, 2012-2015Data
Data Supporting Walrus Areas of Use in the Chukchi Sea During Sparse Sea Ice CoverData
Pacific Walrus Coastal Haulout Occurrences Interpreted from Satellite ImageryData
Walrus Haulout Aerial Survey Data Near Point Lay Alaska, Autumn 2018 and 2019Data
Behavior of Pacific Walruses (Odobenus rosmarus divergens) Hauled Out on Sea Ice During UAS Overflights, Eastern Chukchi Sea, 2015Data
Walrus Haulout Outlines Apparent from Satellite Imagery Near Point Lay Alaska, Autumn 2018-2020Data
Walrus Haulout Outlines and Count Data Apparent from Aerial Survey Images Collected Near Point Lay Alaska, Autumn 2018 and 2019Data
Variability of Lipids and Fatty Acids in Pacific Walrus BlubberPublication
Pacific Walrus Blubber Lipid Content and Fatty Acid Composition, St. Lawrence Island, 2007-2010Data
Sex and Age Composition of Walrus Groups Hauled Out on Ice Floes in the Bering and Chukchi Seas, 2013-2015Data
Walrus ResearchProject Website

Contacts

Fischbach, Anthony S., 907-786-7145
Jay, Chadwick V., 907-786-7414
Taylor, Rebecca , 907-786-7004

Status: onGoing
Start Year: 2005
End Year: 2024

Project Sites

Collaborators
FWS - Alaska Region

USGS Mission Area and Program
EcosystemsWildlife Program

Major Initiatives
USGS - Changing Arctic Ecosystems Initiative