Predictions about the Pink Salmon Oncorhynchus gorbuscha (Salmonidae) Catches on Iturup Island

Abstract

The pink salmon Oncorhynchus gorbuscha spawners which otolith marks created at fish early age at the Kurils and Reidov fish-rearing stations have been studied; fish breeding data and fishing statistics have been analyzed. At the end of the spawning run of pink salmon, only fish of the fish-farm origin have been caught near the fish-rearing stations. More than that, the pink salmon spawners return to the stations of their release (although with rare exceptions). The catches of the pink salmon on Iturup Island are on average 1.6 times greater in even years than in odd years. The increase of the fish stock in odd years significantly depends on the breeding of juveniles in fish farms. There is a positive statistically significant relationship between the filling of spawning grounds with pink salmon spawners and its catches in the Prostor and Kurilsky bays two years later.