 Feral cats are domestic cats that were born in or have reverted to a wild state . They are unfamiliar with and wary of humans and roam freely in urban and rural areas . The numbers of feral cats is not known , but estimates of the US feral population range from 25 to 60 million . Feral cats may live alone , but most are found in large colonies , which occupy a specific territory and are usually associated with a source of food . Famous feral cat colonies are found in Rome around the Colosseum and Forum Romanum , with cats at some of these sites being fed and given medical attention by volunteers . 
