Unless my villagers are starving, I never choose to eat the whale - I don't think it's worth it. Part of the fun of the game is agonizing over the choices. If you really want to know what the alternatives are, you can search on "whale" and you'll see a post from back in April with a description of the alternatives. Don't go there if you don't want the temptation of knowing what all of the Island Events are, though. It's a MAJOR spoiler.