We used to shoot any feral cat we saw. Cats kill 1.7 billion song birds each year.
...and yet the song birds just keep coming back.
Actually their population numbers are way down. Cats are one reason. Other reasons are the destruction of forests in the tropics (where they overwinter) and carving up the US more and more into smaller woodlots, which lets raccoons rob their nests easier. Night time lighting in cities has increased manyfold in the last 50 years, as has human population, and they get confused and fly into buildings when migrating at night.
