Behavioral Responses of Caribou to Low-Altitude Jet Aircraft.
Abstract
We evaluated the behavioral responses of free-ranging caribou (Rangifer tarandus granti) to low-level, sub-sonic jet aircraft overflights. Overflights were conducted by the U.S. Air Force in 1991 during late winter (April), post-calving (June), and the insect season (July-August). During three 7-10 day field sessions, we recorded the reactions of 268 groups of caribou to 159 overflights by A-10, F-15, and F-16 jet aircraft. Approximately 50% of the caribou showed some degree of overt behavioral response to the overflights, but only 13% of the overflights caused the animals to move. Activity budgets were compared between disturbed and undisturbed groups of caribou; no differences were evident in late-winter, but during post-calving and the insect seasons overflown animals spent less time lying and more time either feeding (post-calving) or walking (insect season). Daily distance traveled was compared for disturbed and undisturbed animals; no differences were evident during late winter and the insect season, but disturbed caribou traveled farther than did undisturbed caribou during post-calving. We concluded that behavioral impacts generally were mild, but that female caribou reacted to jet aircraft overflights by lying less and moving more, and that these responses were most prevalent in June when new born calves were present.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1993
- Accession Number
- ADA292491
Entities
People
- Julie A. Kitchens
- Michael D. Smith
- Robert G. White
- Stephen M. Murphy
Organizations
- University of Alaska Fairbanks