There's a trial going on right now in Galveston, TX. You may have heard about the man, James Stevenson, who shot and killed a cat because he claimed it was stalking endangered birds. He admits to killing the animal, and even to the act being premeditated, but he insists he was doing it to protect the birds. Apparently the case has drawn attention from bird lovers and cat lovers alike, and both sides are strident in the defense of their positions.
I myself am a cat person. In fact, my care for birds is so low that I even consent to eat the chicken and turkey variety. So of course I think this guy deserves to be punished. The key factor in the case, which will determine whether or not he is convicted, is whether or not the cat was feral, or belonged to someone. It lived under a bridge, so was not a traditional pet, but the bridge's toll taker did feed it and provide toys, so in my opinion, that makes the cat his pet.
However, I do see his point about the cat being a problem for the birds. But isn't that nature's way? It's one thing when a species is bordering on extinction due to human destruction of its habitat, but when the animal's own natural predators are to blame, I think that's called "survival of the fittest."
Here's the link to the article in the NY Times (free registration required), if you care to read more.