Fewer big and old Chinook salmon in the Pacific

Chinook salmon (king salmon) are the most prized salmon in the Pacific because of their large size. But now an analysis shows that the oldest Chinook salmon are disappearing, and their size is also declining, and these patterns are seen from California to western Alaska and in both wild and hatchery Chinook salmon. The research by SAFS researchers Jan Ohlberger and Daniel Schindler, and their coauthors Eric Ward and Bert Lewis, appears in the journal Fish and Fisheries, and was highlighted in UW News.

The number of Chinook salmon returning to spawn that spent 1, 2, 3, 4, or 5 years in the ocean. The largest returning fish are those that spent five years in the ocean.
Declining size for each group of returning Chinook salmon, showing the declines in size of salmon returning that spent 3, 4, or 5 years in the ocean.
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