Captivity
 

Anyone have an idea on how long you can keep a wild caught animal in captivity before it loses its instincts and cant be returned to the wild?
I'm just asking because i have to present to some students and wasn't sure if i could start herping now and hold on to the herps just until the end of april. Thanks

You probably don't have to worry about them losing their instincts in that amount of time. In fact I bet if you turned a 5 year old cornsnake born in captivity loose it would have a good chance of surviving. Instinct is about all they have.
What you do need to worry about is introducing something to the wild.
I'd maintain all snakes captured seperately in strict quarrantine, for their sake as well as that of your personal collection. Also keep track of where individuals were captured so they could be returned there.