how do know that black rat snakes are at risk?

Answer 1

The black rat snake, Elaphe obsoleta, one of the largest snakes in the United States, reaching a length of eight feet, is an uncommon species, as indicated by how rarely they are seen. Forty to fifty years ago the species was quite common. As a boy growing up in New England with an interest in herpetology, I caught several of them, and observed several more. Today it is a rare occurrence to catch a glimpse of one.

Answer 2

Your question is too vague- you're going to have to elaborate. Black rat snakes are at risk...of what?