In this unusual diet shift, the animals have pursued a prey they normally chase significantly farther north, up the California coast or beyond. The expanded menu most likely reflects fluctuation in the local anchovy population, experts say. For whale enthusiasts, the switch has provided excellent viewing opportunities. Benko described a feeding frenzy that surrounded his vessel this week. They were using the boat to feed.
Humpbacks eat by filtering food through baleen plates.
The bubbles rise and trap groups of fish. Then the whales, jaws wide open, swim directly toward their collected prey. On a good day, visitors to the Channel Islands Marine Sanctuary can expect to see 50 or more humpbacks, and even feel mist from their blowholes. We heard humpbacks, we smelled humpbacks . . . Sometimes they would pop vertically out of the water, exposing more than a third of their body length.