Ronas and his girlfriends performing a public service. Two whole longboats full of men ended up in the cold water, and the three whales very helpfully arrange for not a single one of them to suffer from hypothermia.

Of course that could have something to do with them working together to overturn the boats, and for the orcas to herd the men together so that the ones they don't themselves swallow end up in the rising sandworm mouth of the baleen whale to be gulped down in one great wriggling bulk, but helpful is helpful!