Opossums do come with some benefits. Opossums can help keep your garden in check by slurping up snails and slugs. They'll also assist you in pest management, frequently eating common pests and disease carriers like rats, cockroaches, and mice.   And because these critters are resistant to snake venom, poisonous snakes hiding in your grass can make an excellent food source for a hungry opossum.   When it comes to preserving or getting rid of opossums, you need to consider what pros and cons are important to you.