[The social organization, behavior and ecological parameters of a migrating population of Siberian roe deer (Capreolus pygargus Pall.)].

Data obtained in 1988-1994 during a long-term study of the ecology and behavior of a seasonally migrating Siberian roe population in Amur Province are reviewed. Aerial surveillance of 24 roe marked with transmitters was used for tracing their migration routes under normal conditions and in the homing experiment. It was found that the routes of roe migrations can be as long as 200 km. These routes, as well as summer and winter territories and the sites where roe cross the rivers, remain unchanged year after year. In spring, roe migrate back along the same route as in autumn. In autumn, the average rate of migration is 6.1 km per day (the maximum rate is 26 km per day), and in summer it is 3.8 km per day. The urge to migrate is apparently innate. The roe memorize the route followed once and are capable of orienting themselves on expanses of land. The first frosts provide a stimulus for autumn migrations. Most roe start to migrate 30-45 days before the formation of snow cover, when forage is still abundant. This fact contradicts traditional views on roe migrations, which fall into the following scheme: thick snow cover; the absence of forage; migrations. A new hypothesis concerning the evolution of roe migrations is proposed. The social, sex, and age structures of the population are analyzed.