If you want a healthy, affectionate cat, get it while it's young and keep it in your house.
The statistics on the killing of birds by cats are appalling. A pair of birds works hard to raise fledglings, then a cat comes along and kills the naive young as soon as they leave the nest. In time, the adult birds die and there is no one left to continue the lineage.
Why? Because the owner is too lazy or too silly to keep the cat where it belongs.
Meanwhile, the cat is endangered by fleas, tapeworm, feline leukemia, cars, dogs, cat fights ...