Dynamics of abundance for pink salmon Oncorhynchus gorbuscha (Walbaum) in the Tauyskaya Bay (Okhotsk Sea) under conditions of global climate variability

Dependence of the pink salmon year-classes strength in the Tauyskaya Bay on the number of parents and weather factors during the freshwater period of life is analyzed. For the Ola population of pink salmon (in the Ola and adjacent rivers), such dependence can be described rather well by Ricker equation. Over the past century, deviations from this equation have been statistically correlated with autumn precipitation in the year of spawning, but this relationship has gradually weakened with climate warming, while the dome-shaped correlation with summer air temperature in the same year has become stronger. A statistical model is proposed that considers all three factors and satisfactorily simulates dynamics of the year-classes. Dynamics of the Taui population (in the Taui and adjacent rivers) in the current century is described by a similar equation. Possible reasons for alternation of strong and weak year-classes are discussed, as well as the cases of change the cycles of domination for odd either even year-classes and possible consequences of climate warming. Methods for forecasting the pink salmon approaches are proposed.

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