September 16, 2009
Whale Wednesday: Stuck on Salmon
New research out of Canada indicates that some killer whale populations prefer king (a.k.a. Chinook) salmon so much that the whales will actually die when salmon numbers fall. Here’s the curious part: killer whales, as apex predators, have their pick of other fish or even other large marine mammals, but still some populations appear to be dependent upon king salmon as their primary food resource. Another study from Hawaii found that killer whales can identify king salmon even when they are swimming alongside Coho and Sockeye salmon. And even in the winter, when king salmon make up just 10 to 15 percent of the salmon in the water, killer whales use echolocation to pick out their favorite fish. That’s some impressively picky eating. A recovering picky eater myself, I fully relate. And king salmon are undeniably delicious. Who can blame them? But suffering king salmon populations spell trouble for the orcas. The pollock industry catches enormous amounts of king salmon as bycatch. And due to the low populations, the 2008 king salmon fishing season was cancelled in Oregon and California, and again in 2009 in California. With king salmon lovers abound on land too, something’s gotta give.