My dad had a green tree frog living in his engine bay for a couple of years. It came home from Queensland with him one christmas, lived there through a Melbourne winter, went back to Queensland again, came back to Melbourne again for another winter and then back to Queensland to stay 2 yeras after first jumping on board.

Dont know what it ate or how it survived winter down here, or how it never fell out while he was driving around. Hardy little critter it was.