Snakes don't chew on wiring, shred life jackets and carpet for dens, have large litters of babies multiple times per year, or pee near straight ammonia (which can be corrosive). Mice, rats, and squirrels do. I'd far rather have a rodent-repelling nonvenomous snake in my boat than rats, mice or squirrels.

How about trying to find out about the snake, because it could quite possibly do you zero harm and provide an actual benefit. There are plenty of snake identification sites that will help you figure out what you have. If it's nonvenomous (and it probably is), leave it alone. It will find its way out.