About ten years of age, this neighborhood cat is a killer.... quietly stalking every inch of his territory. An amazing and shy animal, which when coaxed, will roll beneath a hand and purr like a kitten... I have seen him in younger days take a bird from flight, meander under a bush and relish every bite. Perhaps it's freedom and a "natural" diet which keeps him young... A cat reaches the approximate human age of 15 during its first year, then 24 at age 2. Each year thereafter, it ages approximately four “cat years” for every calendar year. Thus, a 5-year-old feline would be approximately 36 in cat years. http://www.catster.com/cats-101/calculate-cat-age-in-cat-years