Many new owners are worried about being bitten by their rat. Actually, rat bites are relatively unusual. Some rats do bite, however. A rat who keeps biting may do so for a number of reasons.
The most common form of rat biting is test biting. This is not really biting and has more in common with the mouthing that young puppies do than a true aggressive bite. Rats explore with the mouths, and they gently ‘bite’ to see what you are. This is especially common in young rats.
If a test bite is too firm for your liking, squeak loudly. This is how another rat would let them know the bite is too hard.
Rats use their teeth when they groom themselves and each other. Grooming is social behaviour, so your rat may use their teeth when grooming you too. Rats have fur to protect them from their friends’ sharp teeth, whereas we don’t, so what your rat intends to be a social gesture can feel uncomfortable or even painful to us. As with test biting, teach your rat what is too hard by squeaking.
Some rats will bite from aggression. If you aren’t sure if a rat is biting you for this reason, look for other signs of aggressive behaviours, such as sidling or fluffing.
The rat may have an aggressive nature, or the aggression may be caused by something else. some rats experience ‘cage aggression’. If your rat is perfectly friendly outside the cage but bites aggressively in the cage, this might be the problem. Rats can get territorial and perceive your hands in the cage as a threat. Try to get your rat used to you being in the cage with taming activities. Don’t teach your rat that they can get their own way by biting. If a rat bites you to get you out of the cage, grab the rat and firmly tell it no before releasing it. If you need to get a cage aggressive rat out of the cage, you can compromise by training it to climb into a tube or carrier instead, so you can lift it out while still sparing your fingers.
Hormones can also cause a rat, especially the male, to become aggressive. An aggressive buck can benefit from being neutered. This can help with a rat who is aggressive to humans or his cagemates. Females are usually less affected by hormones, but a spay can help with some aggressive does.
A rat may also bite in fear. if a rat who is usually friendly bites you, think about whether you may have startled it. New, untamed rats may also fear bite at first when handled.
Try not to startle your rats. All rats have poor eyesight, but red and pink-eyed rats have even worse sight. Try to make a noise such as tapping on the side of the cage before touching your rat so you know it knows you’re there.
If you’re working with nervous rats, the biting should stop as you progress through hand-taming them.
Rats may bite for other reasons too. A rat who mistakes fingers for food may snatch at you through the cage bars. Don’t feed treats or any other food through the bars and always be careful when poking your fingers through the cage bars.
Some rats will pull at things that feel don’t belong with their teeth. It’s common for rats to try to take out earrings, pull off plasters and bite at long fingernails. Some rats also object strongly to socks and will nip your feet if you’re wearing socks. At Rattie Ratbags, we call this sock monsters.