Decreasing of the Pink Salmon (Oncorhynchus Gorbuscha) Abundance in Sakhalin-Kuril Region as Consequence of Extreme Environmental Factors Impact

The pink salmon abundance dynamics is considered for Sakhalin-Kuril region in 2007–2016. The year-classes of pink salmon originated from Iturup Island and four areas of eastern Sakhalin became weaker if they were affected by typhoons during their embryonic development in rivers (spawning nests) or feeding of the juveniles in the coastal sea soon after their downstream migration from the rivers. That means that extreme environmental events are the most important for formation of the pink salmon abundance. The pink salmon runs to these areas in 2017 were successfully modeled using this dependence.