I never understood why. They dont compete for food and 9 times out of 10 a feline cannot catch a bird. Or sometimes its just not worth the effort. An ostrich can break the back of a lion with one kick for example. Maybe cartoons started it but I dunno its more believable for reptiles to be the enemies of cats and birds. Snakes actually go after both.
>>725506635 (OP)
Cats are kind of everything's mortal enemy.
Cats caused more animal extinctions than any other animal excluding humans. Hell, they might have caused more than humans but since they aren't cutting down trees they are more subtle about it.