My class at OIMB went whale and bird watching offshore one last time. We saw a transient group of orcas--two females and one male. They were swimming in circles with what looked like an orca calf. Then one of the females charged out of the water, tossing this harbor porpoise. My classmate, J. Goodell, happened to turn her camera on at the right moment and got this shot. I don't think that I will see anything like this again.Notes on orcas:
There are two resident populations of killer whales in the Pacific Nortwest: Northern (Vancouver, BC to Alaska) whales and Southern (Puget Sound to S. Vancouver island) whales. Residents normally eat fish like salmon. Transient killer whales normally eat marine mammals. When they catch mammalian prey they toss it around for awhile, much like a cat tends to toss around a mouse before eating it. Not much is known about the reasons for this behavior. Perhaps they are teaching their young how to hunt. Another hypothesis is that they jolt the blubber free of the rest of the carcass while tossing prey (thus making it easier to bite off the best part of the animal:fat). Maybe it's fun to do.
Also, killer whales are opportunists. They will eat bottom fish, whale carcasses, seals and sea lions, and less commonly polar bears and moose. Orcas in Patagonia are known to strand themselves on the shore in order to catch a meal. If I had to choose between swimming in orca territory or shark territory, I would choose sharks.
If you click on the photo, it should get larger. It's amazing that we even got to see it, so I am happy with a grainy photo.
