Green Stray Cat, Varna, Bulgaria

• Life span and survival
Feral cats in managed colonies can live long lives. A number of cats in managed colonies in the U.K. died of old age. In the U.S., the last cat in a managed colony in Washington, D.C. died at age 17; and Zorro, the last cat of a colony at the Merrimack River in Newburyport, Massachusetts, died in 2009 at age 16.
A long-term study of a trap-neuter-return (TNR) program in Central Florida found that despite widespread concern about the welfare of free-roaming cats, 83% of the cats studied had been present for over six years, with almost half first observed as adults of unknown age. These time spans compared favourably to the average lifespan of 7.1 years for pet cats reported in a 1984 study, and to the finding that only 42% of the pet cat population in the U.S. is more than 5 years old.
Without human assistance, feral kittens are expected to have a high death rate.