I keep ferrets, rats, and BPs in the same room. The snake rack door gets closed when ferrets come out for play time.
Ferrets would kill a ball python hands down. They would do it accidentally by trying to play with it too hard. Unless it was a feeder prey, they wouldn't viciously kill the snake on purpose. But the snake would be dead at the end of the day regardless.
Plus balls probably won't see the ferrets as prey anyway and wouldn't try feeding on them. They look and smell totally different from rats and mice. And they are already really picky with their food anyway.
Now if we are talking about other species of large constrictor, the snake would kill the ferrets in an instant. They're less picky in prey.
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