Polar Bear Electronic Deterrent and Detection Systems
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 […]
The Estimation of Survival and Litter Size of Polar Bear Cubs
The mark/recapture analyses that are currently used to study polar bears (Ursus maritimus) generally underestimate the average number of cubs per litter and assume that the annual survival of cubs is unity. In this paper, a relationship among the number of yearlings per litter and 2-year-olds per litter is used to derive the survivorship of […]
Use of Sea Ice Habitat by Polar Bears
Use of habitat by polar bears (Ursus maritimus) on coastal sea ice was investigated through observation of undisturbed polar bears and their environment. Nearshore sea ice was kept under 24-hour surveillance from 4 field camps established successively from 19 May to 19 July 1979 on island coasts bordering Barrow Strait, Northwest Territories, Canada. Two of […]
Behavior of Polar Bears with Cubs in the Denning Area
Observations were made on the behavior of female polar bears (Ursus maritimus) with cubs of the year in the first post-denning period in a densely populated denning area at Kongsoya, Svalbard. This period has formerly not been studied. During 2 field seasons 3,148 hours of observations on females, and 6,185 hours on cubs, were obtained […]
Productivity and Maternity Denning of Polar Bears in Ontario
Aerial surveys to assess polar bear (Ursus maritimus) productivity were conducted along the northern coast of Ontario during February and March, 1974 through 1978. Cub production varied from 33 to 112 annually, and averaged 71 during the 5-year period. Average litter size was 2.0. Emergence extended from late February to early April with the peak […]
Satellite Radio-Tracking of Polar Bears between Svalbard and Greenland
An aerial survey program in 1977 and 1979 revealed that tracks of polar bears (Ursus maritimus) were abundant from Svalbard to Northeast Greenland south of 81° north latitude. In order to obtain evidence on possible exchange of polar bears between Svalbard and Greenland, 4 bears were instrumented with satellite radio collars from the ice drift […]
Diel Activity of a Remnant Population of European Brown Bears
The temporal distribution of activity and rest over the 24-hour cycle is characteristic of a species and, to some extent, a function of the environment. Parameters of this distribution could possibly be used to estimate the stress on a given animal population. To measure the diel activity pattern of the last brown bears (Ursus arctos) […]
Characteristics of Summer Beds of European Brown Bears in Norway
One hundred and nineteen European brown bear (Ursus arctos arctos) daybeds and their surroundings were studied in Hedmark County, Norway, in 1974-77. In addition to bed type and size, the following parameters were measured or estimated: slope, aspect, altitude, type and age of vegetation, cover, distance to close objects, and distance from the site to […]
Grizzly Bear Dens and Denning Activity in the Mission and Rattlesnake Mountains, Montana
Forty-one grizzly bear (Ursus arctos horribilis) dens were found in the Mission and Rattlesnake Mountains, Montana, from 1976 through 1979. Ten of these dens were used by transmitter-equipped grizzly bears. Thirty-nine dens were excavated in open, side-hill park habitat and 2 were under forest canopy. Two dens occurred at 1250 m while 39 were between […]
Bear-Sheep Interactions, Targhee National Forest
Black bear (Ursus americanus), grizzly bear, (U. arctos), and domestic sheep interactions and competition were investigated using radiotelemetry on the Targhee National Forest in Idaho and Wyoming during 1976 and 1977. (Black and grizzly bear intra- and interspecific relationships are discussed in terms of habitat utilization.) Radio-monitored movements of 7 black bears and 1 grizzly […]
