Do Pet Rats Bite?

To my knowledge, rats are the least likely pocket pet to bite. This makes rats, in my opinion, better pets than hamsters. Even wild rats, despite their bad reputations, are not likely to attack humans. Yet, I still frequently get asked by non-rat people if my rats bite.

I really hate this question. Why? Because the question isn’t just about my rats, but whether all pet rats bite. I also find it odd that people think I may have dedicated my life to an aggressive pet. In truth, there’s way more nuance to this question than I can answer in a brief conversation. I know people who ask don’t want my full answer, so I just say “no.” This is technically true. None of my rats are biters, but I have been bitten by some.

If I were allowed to give my full answer when asked, “Do rats bite?” this article encompasses much of what I’d say.

Questions To Consider If A Rat Bites

Yes, some pet rats do bite. But the reason why they bite is important. Knowing the cause helps an owner or prospective adopter figure out what to do next. Ask yourself the following questions:

1. Was the bite a one-time occurrence? Because one or two bites does not a biter make. If biting is a new habit, however, then there’s an underlying reason that needs to be explored.

2. Does the rat only bite in the cage? Some rats are perfect angels outside of their cage but are little devils inside it.

3. Is the rat really biting? You’d be surprised how many misunderstandings or self-fulfilling prophecies occur because of a person’s fear of being bit.

4. Is there a way to stop this behavior if a rat is a serial biter? I believe that most rats who bite can be reformed. It just takes work and dedication by you.

So, what might cause a rat to bite in the first place?

Bites Caused By Fear

Fear is probably the No. 1 reason a rat might bite. This does not mean that all fearful rats bite. I have rescued rats from some pretty horrible situations of neglect, abandonment, hoarding, and mistreatment. Despite their understandable fear, none have been biters. Frightened rats, wild or domestic, almost always try to flee a situation that scares them rather than be confrontational.

There are some rats, however, for whom biting feels like a necessity for survival. They were likely abused and/or are suffering a PTSD-like anxiety from a human or predator. These rats are just very, very scared — not mean. I believe that these rats are not lost causes and can be worked with by the right owner.

Rats With Cage Aggression

Some rats are like Dr. Jekyll and Mr. Hyde when it comes to their cage. Outside of the cage they are usually very sweet and loving. In their cage, they rage like Mr. Hyde and attack. This is likely caused by some sort of trauma they’ve experienced.

Years ago, I helped my mother with a foster group of rats that were taken from an uncaring feeder breeder. The rats were infested with lice, malnourished, and had never really been played with or held. Surprisingly, they were quite sweet despite their former life. It didn’t take long to earn their trust — except for the “momma” of the group. She carefully watched us from the cage, and charged up the ramp ready to attack when we opened the door.

It took us awhile to learn that outside of her cage she was just as gentle as the other rats and nothing like the angry little beast she was inside it. As we learned more of her backstory, we discovered that she had been forced into pregnancy over and over and over again. Each time her babies were abruptly snatched away from her. She now viewed hands reaching into her cage as a threat. She had had enough! There was no changing this girl’s mind, so we just adapted to her needs. We found ways of getting her to come of the cage on her own, which allowed us to play with her and clean the cage when needed.

So, was she a biter? Yes. But was she also not a biter? Yes — as long as she wasn’t in her cage.

The Hormone Effect

Male rats hit social maturity between 5 to 6 months old. This results in hormonal changes that can show up as late as 9 months old. These changes can cause some rats to act aggressively, especially toward their cagemates. Sometimes it also results in biting the owner. I’ve had numerous males go through this transformation, but only one actually started biting me. Castration calmed him down, and he never bit me again.

Biting Caused By Health Issues

Rats can’t verbalize how they feel, so if one suddenly starts to bite, it could be an indicator of pain and/or illness. Neurological illnesses, such as a pituitary tumor, can also change your rat’s personality and cause aggression. Depending on the cause, biting might only be temporary. But the only way to know or help is to have your rat evaluated by a vet.

Bad Breeding

Many rats are bred as snake food and for pet stores. Little thought is put into the genetics or the health of these rats. This means that a rat known for biting might still be used for breeding. There’s a chance this behavior will be passed on to the offspring.

This does not mean, however, that all rats bred this way will be aggressive. There is no difference between a “fancy” rat and a “feeder” rat. Forget how they are labeled by a store or breeder. All domesticated rats are technically “fancy” rats — and even “feeders” can make amazingly loving pets.

Was It A Bite?

The director of Any Rat Rescue told me once that the majority of rats dumped on them because of biting rarely show signs of actual biting in their care. Did they magically just stop biting, or did they ever really bite in the first place? I personally believe that many newer owners misunderstand rat behavior and interpret nibbling, playfulness, and curiosity as aggressiveness.

Rat Behaviors That Are Confused As Bites

Grooming: Some rats also like to nibble on human nails or clean their owners. Rats often groom each other using their teeth in a fast, nibbling action called allogrooming. Some rats do this to their humans, too. Is it comfortable on human skin? No, not always, especially if it’s in an area where the skin is thinner or more sensitive, but this is not an act of hostility. They just think of you as part of their pack.

Learning Social Skills: Some young rats mouth fingers or skin as they learn social skills. Even if their teeth come in contact with your skin, it’s doubtful they actually bite down. It’s like a puppy or human baby tasting and testing things. Or they might nip in an attempt to play, but they are unlikely to break the skin.

If this occurs, the best thing to do is say, “no” or “gentle” to your curious, playful rat and either leave your hand still or slowly move it to pet them. Keep calm and show affection to set the mood to teach them proper socialization.

Poor Eyesight: Rats have very poor eyesight, but a great sense of smell. Plus, they can be a bit greedy about food. These things combined lead to one of the largest misunderstandings about biting. If your fingers smell like food, they can’t necessarily see the difference. Depending on how grabby your rat is, this could result in a chomp to a finger. This is especially possible if you’re handing an overly grabby rat a treat. I’ve learned real quick which rats of mine to be cautious with when it comes to hand-feeding.

I always tell owners NEVER to feed their rats through the cage bars because it teaches the rats to grab anything near the cage, even skin. Again, this is not due to aggression; it’s really about poor eyesight. It’s easy to work around though, so it should never be a reason to not have rats or to get rid of yours.

Human Fear: Years ago, I adopted a rat from my local humane society after I learned he was likely to be put down due to biting. His original owner proclaimed him vicious. The shelter volunteers, who had little experience with rats, refused to go near him. This rat spent a year of his life stuck in a tiny cat carrier with no rat friends and was completely neglected by his fearful owner before being dumped at the shelter. So, it was no surprise when he screamed in fear the first time he met me. Yet, he did not bite me.

Because I was told he was biter, I was cautious about putting my hands near his face as I worked on trust training. For the first couple of days, he screamed bloody murder and cowered in a corner of his cage any time I opened the door, but he never once made a move to bite. After three weeks of trust training in my bathroom, he finally felt safe. He became one of the most cuddly, gentle rats I’ve ever been blessed to love. And not once did he bite me. To this day I cannot figure out why he was labeled a “biter.” It grieves me to know that he was almost put down because of it. Or that he almost missed experiencing happiness, due to a misplaced fear people had of him.

Don’t Give Up On Them

The assumption that a rat will bite often dooms these precious creatures to a life of neglect, mistreatment, abandonment, or euthanasia. This all has the potential of creating fearful and unsocialized rats. Don’t let self-fulfilling prophecy change them!

If a rat does bite, it doesn’t mean they’re a lost cause. Even serial biters can be worked with through patience and commitment. The first thing to do is talk to a vet about possible medical causes and castration. Then research trust training for traumatized rats or reach out to shelters or other rat owners with experience. There is no greater feeling than watching a frightened rat learn they are loved!