ИСТИНА

Populations of Arctic charr Salvelinus alpinus complex listed in the Red Data Book of Russian Federation as S. a. erythrinus, from five mountain lakes of Northern Transbaikalia were studied from 1977 to 1999. The lakes are situated at the watershed of rivers Kuanda (Vitim-Lena basin) and Chara (Olekma-Lena basin) in the vicinity of the Baikal-Amur railway constructed in this region in early 1980-ies. In each of them two or three sympatric charr forms (dwarf, small, large) differing in size at maturity were found. Data on age, growth, repro- duction, feeding of these forms as well as on the food resourses of the lakes are presented; changes in charr populations over the study period due to anthropogenic factor were monitored. The large form of charr in Lakes Bol'shoe Leprindo, Maloe Leprindo and Gol'tsovoe and the small form in the latter were exterminated by illegal fishing which considerably increased after the construction of the railway; in Lake Leprindokan the abundance of the large form sharply decreased.