M.C.
Check your contract, and make sure you have included the right to enter the premises.
If you did, send one of your friends on your behalf to take pictures of the current damage. (As well as the excess animals, if you have that out in writing as well.) then you can have a record if they start purposely destroying things that they did it as retaliation for being kicked out. I'm not sure about the laws where you live, but my grandma is able to charge her ex-tenants for damages beyond normal wear and tear if the amount exceeds the deposit. Especially if they are breaching the contract with their animals, and those animals are the cause of the damage. Granted, you will want a LOT of documentation, and it would most likely have to go to court... So really, that course would depend on just how much damage there is. My grandma usually just eats the cost because it's such a hassle... But she has dragged a few people to court over extreme damages. (And won, too.)
Be very careful what you say as a reference... Give facts, and only facts. Do not allow your personal feelings to give them a reason to claim you slandered them. Try to get proof of the facts ASAP, so you can use them without fear of repercussion.
ETA: I know that any time I have rented, the contract automatically converts to month-to-Minh when the lease is up. If it isn't specified in your contract, definitely look up the default laws for your area.