Also, feral cats eat what they can; a diet that sometimes includes songbirds and lizards. That's why in recent years, there's been a line drawn outside the cat box. On one side stands the bird groups, such as the American Bird Conservancy and the National Audubon Society. On the other side are feral cat advocacy groups like Alley Cat Allies, who support trap, neuter and return (TNR) programs.
The grass-roots TNR programs are supported by animal shelters and volunteers who humanely trap feral cats to be spay/neutered; vaccinated for rabies, often microchipped and ear-tipped (so caretakers know which have been spay/neutered). TNR is humane, and obviously if all the cats in colonies (their social groups) are altered, their population ultimately dwindles.
Also, many TNR groups supplement their colonies with food, so the cats are less motivated to kill as much wildlife.
However, feral cats remain the object of outright hostility by the bird groups, who call TNR an abject failure, and attempt to find fault anywhere they can. On Sept. 21, the American Bird Conservancy issued a press release entitled, "Feral Cat Colonies Present Perfect Storm for Rabies Risk."
The release also states: "According to the Centers for Disease Control and Prevention, most people are exposed to rabies due to close contact with domestic animals, such as cats and dogs."
This is true, but that definition doesn't include feral cats. While feral cats are considered a domestic species, the CDC is referring to pet dogs and cats.
Because they are cats, the press release notes that they are perceived as domestic, and approachable. Perhaps they're domestic, but feral cats are not approachable.
While formerly owned cats might not run off, feral cats might not scamper away from people they know, such as colony caretakers. Also it's true that some cats have been identified with rabies.