If you have trees, you will get to know squirrels. You may marvel at their antics, until they take over your bird feeders. Then you'll either love them or hate them.

Those who love squirrels tolerate their visits, and may even encourage them with special squirrel toys and feeders.

When a squirrel is at the feeder, you're not likely to see birds. Squirrels will scare off the birds while they eat the seed, and sooner or later, they'll eat the feeder too.

The simplest solution is the squirrel-proof feeder or pole, and storing your seed in a metal garbage can.

Chipmunks, rats and mice can also become a problem where there's seed spillage under the feeder. Don't use mixed bird seed, and if you don't have a squirrel problem, add a feeder tray.

Crow, house sparrow and starling problems can be eliminated by seed and feeder selection.

Cats are another story altogether. Feral cats and your neighbor's tabby are a serious threat to nestlings, fledglings and roosting birds. Too often, the presence of just one cat on the prowl near your feeder can take the enjoyment out of your backyard bird watching experience.

When a cat sits drooling under your feeder, you're not likely to see any birds. You're bound to feel much worse when you find a pile of feathers on the ground.

If your neighbor is reasonable, suggest a bell collar. If that doesn't work, consider getting yourself a pet -- a dog. Birds don't seem to be bothered by most dogs, but cats and squirrels are.

If there are no cats in your neighborhood and you find a pile of feathers near your feeder, look for a hungry hawk perching on a tree nearby.

Don't get upset. Consider yourself fortunate to see one, right in your backyard. Cooper's and sharp-shinned hawks eat birds and play an important role in the natural community.

Don't put out poisons, or try to trap them, especially since all birds of prey -- eagles, owls and hawks -- are protected by Federal law.