A review of the Sea of Okhotsk ecosystem response to the climate with special emphasis on fish populations

Abstract

This article provides a brief review of climatic, oceanographic, and biological changes in the Sea of Okhotsk in recent decades. The Sea of Okhotsk is distinguished by its high biological productivity and its significant impact on the Pacific Ocean through water exchanges. Long-term temperature data have shown periodic cooling and warming of the Sea that in turn have resulted in changes to its biological communities. In the 1980s, a generally warm period, the Sea of Okhotsk had abundant fish, primarily large stocks of gadoids, especially walleye pollock. The second half of the 1990s was a transitional period when the marine ecosystem was being restructured. In particular, by the mid-1990s, the total biomass of fish in the Sea of Okhotsk had decreased significantly. In the early 2000s, the situation reached a critical level, but by the end of that decade, there was a renewed warming and an increase in the abundance of walleye pollock. © 2012 International Council for the Exploration of the Sea. Published by Oxford University Press. All rights reserved.