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USGS · 70131502

Response of Yellowstone grizzly bears to changes in food resources: A synthesis. Final report to the Interagency Grizzly Bear Committee and Yellowstone Ecosystem Subcommittee

Interagency Grizzly Bear Study Team·Frank T. van Manen·Cecily M. Costello·Mark A. Haroldson·Daniel D. Bjornlie·Michael R. Ebinger·Kerry A. Gunther·Mary Frances Mahalovich·Daniel J. Thompson·Megan D. Higgs·Kathryn M. Irvine·Kristin Legg·Daniel B. Tyers·Lisa Landenburger·Steven L. Cain·Kevin L. Frey·Bryan C. Aber·Charles C. Schwartz
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Abstract

The Yellowstone grizzly bear ( Ursus arctos ) was listed as a threatened species in 1975 (Federal Register 40 FR:31734-31736). Since listing, recovery efforts have focused on increasing population size, improving habitat security, managing bear mortalities, and reducing bear-human conflicts. The Interagency Grizzly Bear Committee (IGBC; partnership of federal and state agencies responsible for grizzly bear recovery in the lower 48 states) and its Yellowstone Ecosystem Subcommitte (YES; federal, state, county, and tribal partners charged with recovery of grizzly bears in the Greater Yelowston Ecosystem [GYE]) tasked the Interagency Grizzly Bear Study Team to provide information and further research relevant to three concerns arising from the 9th Circuit Court of Appeals November 2011 decision: 1) the ability of grizzly bears as omnivores to find alternative foods to whitebark pine seeds; 2) literature to support their conclusions; and 3) the non-intuitive biological reality that impacts can occur to individuals without causing the overall population to decline. Specifically, the IGBC and YES requested a comprehensive synthesis of the current state of knowledge regarding whitebark pinbe decline and individual and population-level responses of grizzly bears to changing food resources in the GYE. This research was particularly relevant to grizzly bear conservation given changes in the population trajectory observed during the last decade.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 42.90816007196054° to 45.79050946752472° latitude; -112.3681640625° to -108.3526611328125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Interagency Grizzly Bear Study Team, Frank T. van Manen, Cecily M. Costello, Mark A. Haroldson, Daniel D. Bjornlie, Michael R. Ebinger, Kerry A. Gunther, Mary Frances Mahalovich, Daniel J. Thompson, Megan D. Higgs, Kathryn M. Irvine, Kristin Legg, Daniel B. Tyers, Lisa Landenburger, Steven L. Cain, Kevin L. Frey, Bryan C. Aber, Charles C. Schwartz. 2013. Response of Yellowstone grizzly bears to changes in food resources: A synthesis. Final report to the Interagency Grizzly Bear Committee and Yellowstone Ecosystem Subcommittee. https://pubs.usgs.gov/publication/70131502

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Factors affecting benthic macroinvertebrate health in the City of Roanoke, Virginia, 2020–2023

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