Endangered Southern Resident killer whales prey on a diversity of Chinook and other salmon. The stocks come from an enormous geographic range as far north as Alaska and as far south as California’s Central Valley, a new analysis shows.
The diverse salmon stocks each have their own migration patterns and timing. They combine to provide the whales with a “portfolio” of prey that supports them across the entire year. The catch is that many of the salmon stocks are at risk themselves.
“If returns to the Fraser River are in trouble, and Columbia River returns are strong, then prey availability to the whales potentially balances out as the whales have evolved to move rapidly throughout their range,” said NOAA Fisheries wildlife biologist Brad Hanson, lead author of the new research. “But if most of the stocks throughout their range are reduced then this could spell trouble for the whales.”
Read more at: NOAA Fisheries West Coast Region
Endangered Southern Resident killer whales prey on salmon throughout the year, diversifying their diet when salmon presence declines. (Photo Credit: Candice Emmons/NOAA Fisheries and reference NMFS permit number 16163)