Grizzly bear use of army cutworm moths in the Yellowstone Ecosystem

Bears: Their Biology and Management
By: , and 



The ecology of alpine aggregations of army cutworm moths (Euxoa auxiliaris) and the feeding behavior of grizzly bears (Ursus arctos horribilis) at these areas were studied in the Yellowstone ecosystem from 1988 to 1991. Army cutworm moths migrate to mountain regions each summer to feed at night on the nectar of alpine and subalpine flowers, and during the day they seek shelter under various rock formations. Grizzly bears were observed feeding almost exclusively on moths up to 3 months each summer at the 10 moth-aggregation areas we identified. Fifty-one different grizzly bears were observed feeding at 4 of these areas during a single day in August 1991. Army cutworm moths are a preferred source of nutrition for many grizzly bears in the Yellowstone ecosystem and represent a high quality food that is available during hyperphagia.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Grizzly bear use of army cutworm moths in the Yellowstone Ecosystem
Series title Bears: Their Biology and Management
DOI 10.2307/3872725
Volume 9
Issue 1
Year Published 1994
Language English
Publisher International Union for Conservation of Nature and Natural Resources
Publisher location Morges, Switzerland
Contributing office(s) Northern Rocky Mountain Science Center
Description 11 p.
First page 389
Last page 399
Conference Title Ninth International Conference on Bear Research and Management
Conference Location Grenoble, France
Conference Date October 1992
Country United States
State Idaho, Montana, Wyoming
Other Geospatial Yellowstone National Park
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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