cats do not like to eat or drink out of bowls if the sides touch their whiskers.  Also, if a bowl is too deep, the cat may take the food out for convenience.  A wider, shallower bowl will probably eliminate this behavior. Why does a cat chatter when he sees a bird? When a cat kills prey, it bites down quickly several times.  The "chatter" is simulating the cat's behavior at the time of attack. Alternatively (according to a visitor): it's pure and simple frustration. When a cat is stalking or killing a bird, they're almost invariably completely silent. It's when they are shut off from the prey that they chatter. Why do cats like crinkly sounds? Crinkly sounds are similar to the high-pitched noises of rodents, birds, and crickets, so the crisp, crinkly sound of a crumpled piece of paper or walking into a paper bag stimulates the cat's "prey response." Why do cats chew on plants? It could be that the grass helps the cat get rid of fur swallowed while grooming, or that grass provides fiber or vitamins and minerals not found in meat.  Some plants are poisonous to a cat; others are okay for nibbling.