Seasonal changes in elevation and habitat use of the Asiatic black bear (<i>Ursus thibetanus</i>) in the Northern Japan Alps

Abstract

Habitat use by Asiatic black bears (Ursus thibetanus) was examined in the Northern Japan Alps where distinct changes in the vegetation occur with elevation. Seven bears (three males and four females) were radio-tracked for five years. Home range size varied from 32 to 123 km 2 , and bears used habitats at elevations between 600 m and 3,000 m. Bears used higher elevations (2,100 to 2,300 m) in summer (from July 1 to September 10), and lower elevations (1,000 to 1,500 m) in autumn (three months after September 10). Bears foraged in subalpine birch forests, avalanche chutes, or the alpine zone in summer, but moved to the deciduous broad-leaved forests of the montane zone in autumn. Bears spent little time in mid-elevation (2,000 m) coniferous forests. Seasonal movements among habitats at different elevations are likely necessary for survival in marginal alpine habitats.