This is a novel way to deal with an intractable problem.  It is about a group of feral cats in Audubon Circle saving a garden from rats, the neighbors who care for them and a cat rescuer, who appeared out of nowhere to help trap and spay them.
 
On a slightly different, but related subject, the Los Angeles Police Department also uses feral cats to catch rats.  Click here to read the Los Angeles Times story "LAPD enlists feral cats for rat patrol."