Анотація:
The quantity of Castor jiber L. in the upper and middle flow of the river Ubort increased owing to the growth of live-stock of some beaver families that inhibited the river
and migration of animals from the lower flow of the river. At present on the river Ubort
from the vil. Emilchino in the south to the boundary with the Byelorussian SSR in the
north all the territory is populated with the valuable rodent. In autumn 1969 there were
only 220—230 beavers. The further growth in their number is inhibited by the weak forage reserve and negative effect of cattle pasture in all littoral zone. It is expedient to withdraw part of beaver life stock (50—60 individuals) for separation or for skin.