Numbers of salmon returning to Alaska and Washington/Oregon showed opposite patterns from 1950-1990. Salmon returning to Alaska (red line) were low between 1950 and 1976 when salmon returning to the Columbia River (black line and green shading) were high. When Alaskan returns were high after 1980, the Columbia River returns were low. GLOBEC studies revealed, however, that different species of returning salmon in the two regions did not always fit this pattern. Image courtesy of NOAA’ s National Marine Fisheries Service, Alaska Fisheries Science Center.