Structure and Distribution of a Kodiak Bear Population

摘要: Population characteristics of the Kodiak bear (Ursus middendorffi) were investigated in Karluk Lake drainage, a 96-square-mile area within National Wildlife Refuge. The drainage contained 160 bears, for density 1 per 0.6 square mile, although some areas attained concentrations 10 bears mile. mean litter size cubs was 2.36 and 2.17 yearlings. Age-class percentages were: cubs, 26; yearlings, 22; 2 years, 17; 3 10; 4 years old over, 25 percent. sex ratio relatively even younger age-groups, but adults, females constituted 78 This attributed to selective hunting larger males. study conducted obtain information about various population bear. It one phase long-term investigation presently underway Refuge Alaska. data, needed as basis managing hunted trophy purposes, obtained during period 1954-62. DESCRIPTION OF THE STUDY AREA area, encompassing 96 miles, included all except River, which drains system flows 20 miles before entering Shelikof Strait. Lake, 12 long 1-2 wide, is fed by two smaller lakes numerous streams (Fig. 1). Red salmon (Oncorhynchus nerka) spawn water summer fall months. with exception northern southern extremities, surrounded mountains 1,0003,500 feet elevation. Mild temperatures annual precipitation 60 inches promote vigorous plant growth. A large portion covered dense thickets alder (Alnus crispa), willow (Salix spp.), elderberry (Sambucus racemosa pubens). These are interspersed meadows containing grasses, sedges, fireweed (Epilobium angustifolium). Intermittent groves black cottonwood (Populus trichocarpa) found along lakeshores, plants associated alpine zone occur on mountaintops.