The responses of free-ranging polar bears (Ursus maritimus) to acoustic and electrified-fence repellents, and to tripwire and proximity detection systems, were evaluated in a 4-year study. Natural and synthesized acoustic repellents deterred 69% (N = 71) of bears who attempted to enter a test perimeter. Position of speakers, sound amplitude, and the timing of presentations are important factors in the effectiveness of acoustic repellents. A 20-kV electrified fence repelled 35% (N = 52), and a 60-kV fence repelled 33% (N = 6) of intruding bears. Tests on a patch of polar bear fur indicated that a nominal 200 kV is required to reliably deliver an electric shock through the highly insulating hair of this species. Tests on single, double, and triple trip-wire fences yielded a 93% (N = 161) success rate for detecting intruding bears. A proximity (capacitance-sensing) detection system detected 100% (N = 13) of bear entries, but was too sensitive to stray electrical inputs. A modified system in the 2nd season detected 63% (N = 41) of intrusions. Refined versions of these devices could offer significant improvements in safety for personnel who must work in close proximity to free-ranging polar bears, black bears (U. americanus), or grizzly bears (U. arctos).
- Volume 5
- Issue
- Pages 264-269
- Publication Date 1 January 1983
- DOI 10.2307/3872547
- File Size 224.37 KB
- Download