Owning is, like, a human construct man. If you can slaughter a herd of animals without facing any human imposed consequences, it's probably fair within the bounds of language and meaning to say that you own them.
See also: Is it possible to own a cat?
Do I own this T-shirt if it can burn? Do I own this stick or am I just carrying it for a while? Is this my banana, or does everything belong to the universe?