Social Relations among Young Yezo Brown Bears in Captivityl) By

• Main Author: Hiroyuki Masatomi
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Ursus arctos
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.627.5180; http://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/27387/1/15(3)_P401-417.pdf

The brown bear is one of the largest carnivorous animals in the Palaearctic region, and is divided into various subspecies within its wide distribution range. Several writers have recently published excellent works on the habit (e.g. Krott 1962, 1962a), but there are still unsolved problems especially with reference to their social behaviour. In Hokkaido (the northern Japanese island) and the southern Kurile Islands, there is one subspecies of Ursus arctos, U. a. yesoensis Lydekker, whose population has recently been estimsted at about 3,000. Except for a few observations on its general habits (Inukai 1933, 1955), there is no closer study of the social behaviour of this subspecies. This is apparently due to various traits which obstruct detailed observation: viz. the solitary and nocturnal nature of their life, the relatively wide home range in wild forests which makes them difficult to survey, and above all their formidable power which occasionally produces dangerous results especially when man is encountered suddenly. As the first step in studying the sociology of wild Yezo3) brown bears, the author tried to observe their social habits in captivity at the Noboribetsu Bear Garden. Obviously the behaviour which animals show under artificial conditions may deviate considerably from that seen under natural conditions. Yet it is also true that even such animals can provide us with many valuable suggestions as to the basic behavioral trends which likely govern their mode of life, whether in a wild or captive state. The observations were started in Feburary, 1963, but were interrupted the follow-ing January due to circumstantial difficulties. Therefore this paper only deals with the social dominance established in two groups of different age.