Was fishing stoner creek yesterday and caught a couple bass. On two of the fish I caught, while removing the hook I noticed a small green slimy think inside the mouth of the fish. I'm pretty sure they were leaches. I removed the leaches from the 2 bass's mouths and threw the leach back in the water then threw the fish back in the water. They were very hard to pull out of the mouth's of the bass, and when I pulled on them with pliers you could tell they were embedded halfway in the skin of the bass's mouth. I just thought this was weird, and wondered how they got there, of the bass eat them? And could they be of harm to the bass? Thanks