In order to figure out the best way to deal with the ferret biting, you must first figure out WHY is it biting.REASONS FOR BITING
1)PLAY
If the animal bounces at you with its mouth open, war dances and bites you, he or she is attempting to play (to see a ferret playing, click here) and doesn't understand that people skin is not as strong as ferret skin. For instructions on how to teach your ferret how to play nicely, click here.
2)ALWAYS WORKED BEFORE
If your ferret bites you when you are holding him and he wants down, when you are cutting his nails and wants you to stop, when he wants you to pick him up or acknowledge him, he has learned that biting is a good way to get what he wants. You must take care not to reinforce his behaviour (for example, if he bites to get your attention, walk away and ignore him for a few seconds before giving him your attention, if you are holding him, continue to hold him for a few seconds after the bite or place him in a time out kennel for a few seconds, then pick him up again... you get the picture! For more tips, click here.). It is also important to reinforce good behaviour with treats and attention. If, for example, you ferret taps you on the leg instead of biting you, drop what you are doing and give them attention and/ or treats - this reinforces the positive behaviour (not biting).
3)TRIGGERS
Triggers are something which causes the ferret to become incredibly aggravated and lash out. Triggers are generally loud noises such as a dog barking, vacuum or loud squeaky toy. I had one ferret that was set of by one person's high laugh. Not all ferrets have triggers, but if you notice that an otherwise friendly ferret bites only when a specific sounds is heard, odds are that your ferret has a trigger. Behaviour correction does not generally work for triggers - they are simply sounds that the ferret cannot tolerate, like fingers on a chalkboard to most people. Once the trigger sound has been isolated, it is best to avoid the noise if at all possible.
4) FEAR
Best described as the ferret lunging aggressively when cornered. Scared ferrets sometimes fluff themselves up have bottle brush tails. A scared ferret may lunge at you when you attempt to remove them from their cage or pick them up off the floor. If they are afraid for their lives, they may even screech at you. If your ferret is a fear biter, it has likely been mishandled at some point in its life. Fear biters have learned, through experience, that humans are the enemy and, if they give you the chance, you will hurt them. While working with a fear biter can be difficult, most, if not all can be rehabilitated and, once they have learned that you are not the enemy, they go on to make wonderful pets. For information on dealing with a fear biter, see the following blog.
5) PAIN
If a ferret feels uncomfortable or is in pain, it will let you know by telling you the only way that it can - with its teeth. A ferret suffering from an extremely severe flea or mite infestation or a really bad rash, infection or pus build up may bite to let you know that they are uncomfortable and that you should do something to remedy the situation. A ferret that is in pain may bite to let you know. To determine whether a ferret is in pain, look for the following symptoms: watery, squinting eyes, teeth grinding, a hunched posture, tenderness (flinching when touched in an area), they may be protective over a certain part of their body, and/or they may refuse food. A visit to the vet to isolate and fix the problem is essential. Generally, in these cases, once the pain or discomfort is gone, the ferret is more than friendly.
6) DOMINANCE
While this is rare, some ferrets will bite their owners to establish dominance over them. Generally this happens in situations where the ferret was a fear biter or a particularly bratty and nippy kit who bit their owner and had their owner display a lot of fear of the animal following the incident. In other words: the ferret was scared or playing and figured out that the owner was more scared and the ferret was, therefore, dominant over the big human ferret. These ferrets will generally bite to affirm their dominance and should be dealt with using a system of gentle correction. In this situation, it is important for the owner to get over their fear of the animal. If you cannot do this, you may want to consider surrendering the animal to a local ferret rescue with more experienced volunteers that can handle the situation. Generally, a "OW! NO!" followed by a scruff and drag (always gentle - remember, you want to teach the ferret that you are the boss, not that you are to be feared) and, if the ferret persists, a time out. Remember to be consistent with this approach and, as with the "it always worked before", do not give the ferret what it wants if it tries to get it by biting. Remember to reinforce good behaviour such as NOT biting with plenty of treats, toys and attention.
If you are having trouble figuring out why your ferret is biting, try to track the bites. Think that what happened around the time of the bite and what your reaction was. Visit the vet to rule out any potential health issues which could be causing the ferret to be uncomfortable or in pain. If you are absolutely stumped, contact your local ferret rescue - they may be able to give you some insight into the matter.
Good Luck!