Migration

I know I’ve said it before, but I’m saying it again: I just don’t get all this migration business. My person says migratory birds are looking for a place to spend the winter that’s warm and has food. If that’s all they’re after, then I have to ask this: Why don’t they just stay in their own cages? After all, a cage is warm and has a full food dish. On top of that, it probably also comes with toys and a person who gives you treats. And it’s right here. You don’t have to fly anywhere to have all this. Why would any bird want to go anywhere else? I just don’t get it.