I had a hamster who absolutely LOVED to bite! I had to work on what I call "discourage reward" training. Essentially, you can put your hand in the cage, near your hamster, and if he sniffs, licks, or ignores your hand, reward him with a treat. However, if he nips or bites, push him away gently with your hand. Eventually, your hamster will begin to realize that biting is not acceptable, but it does take quite a bit of time and patience. Good luck
