Sucks man, but he has every right to fine you. You signed a contract with him stating no pets and it is what it is. I'm not saying this to be mean or harsh either.
I signed a no pet policy with my landlord for 2 years and I told him hey I got reptiles that stay in cages and I told him how many BPs I had and a beardie. I told him at the table is this cool with you... before I signed, he said you can have any animal you want as long as its in a cage.
He just didn't want cats and dogs pooping and peeing everywhere, he runs a business renting houses and some people are just dirt balls so I don't blame some landlords.
Don't tell him they are a collection that's just silly at this point he just wants them out. What you need to do is show him how they are properly caged and don't stink and cant escape. Offer him some extra cash like 300 dollars for a pet security deposit, if that doesn't work out you gotta move or keep your word on what you signed. Hope some of this helps you out.