Life expectancy of a Butler's Garter Snake?

Question

I finally, after lots of research, came home with a baby, captive bred, Butler's Garter Snake. I'm wandering what the life expectancy is, considering it will have optimal conditions and diet.

Answer 1

The average lifespan is 5 years.

Not sure about in captivity though.

Answer 2

The average lifespan of wild common garter snakes is approximately two years. Most common garter snakes probably die in their first year of life. Common garter snakes reach sexual maturity, and maximum size, at 3 to 4 years of age. The lifespan of common garter snakes kept in captivity is longer, between 6 and 10 years. One captive common garter snake lived to be 20 years old, but few wild snakes live this long