Results of the introduction of the resident form of nerka Oncorhynchus nerka in Tolmachevskoe Lake (Kamchatka)

摘要

Data on the present-day (2003-2007) state of the population of kokanee Oncorhynchus nerka introduced in Tolmachevskoe Lake more than 20 years ago are provided. Since the moment of introduction, the population of kokanee has underwent considerable changes: a decrease occurred in the specific rate of growth, average length and weight of fish in catches, and fecundity. The pattern of feeding changed from planktonic to benthic. Kokanee began to feed during spawning. Spawning shifted to later dates (from the beginning of September to the end of September and beginning of October).