Revealing The Truth of Rat Aggression
Rat aggression is very controversial. Many people refuse to believe the harsh reality of an aggressive rat. However, rose-colored glasses are only hurting the rats as individuals and the species.
Rat aggression is genetic, and there is a lot of science to prove it. This means a rat either has the genes to bite or it doesn’t. A non aggressive rat is happy and will not bite. An aggressive rat, however, has a poor quality of life and cannot be with other rats. A person can’t safely interact with it.
Non-Discriminatory Bites
If a rat draws blood, it is aggressive. If a rat bites once, it can and likely will happen again. The target could be you, their own pups, or another rat. Many people dismissed a rat bite and found a dead cage mate months later. A rat bite to humans can damage nerves, tendons, arteries, and soft tissue, which may need surgery. The nerve damage can be permanent, severed tendons may need reattached, and the scars might never fade. A bite to another rat can be life threatening, requiring expensive surgery to fix, or fatal. A rat who draws blood bites to kill.
Awareness
There is no “Oh it was just one time” “It was your fault, you provoked it” “He was just scared” or any other excuse for a rat bite. Rats are not like dogs or cats who can often learn to stop biting. Either a rat has the genes to bite, or it does not.
A rat knows how much force they are using. If they draw blood, it is intentional. They know food from your finger, even through cage bars. You can put baby food on your finger and they will lick instead of bite because they know your finger is there.
Two Types of Rat Aggression
There are two kinds of aggression. Both can be bred out, but one has a non-lethal solution.
Hormonal
Hormonal aggression in males appears around 6 months of age. It is fixable through neutering. If it does not go away 2 months after neutering, it is normal, unfixable aggression. In females, hormonal aggression (HA) presents as maternal aggression (MA). This appears during pregnancy and nursing. Some unethical breeders try to explain it away as a mom being protective, but maternal aggression is nondiscriminatory. The mother can kill all or most of her pups from it.
The solution for MA females is to stop breeding them. They may be re-homed without risk of biting if they never breed again. No one should breed any pups of a HA female. Watch her male pups for HA development. Female maternal aggression can pass on to male pups as hormonal aggression.
If an unbred female bites, it is general aggression instead of hormonal. A rat can have both hormonal and general aggression. A bred female biting after her pups wean and grow up also has general aggression.
General Rat Aggression
General aggression, often only called ‘aggression,’ can present in both genders of rats at any age. Stress can trigger it, such as re-homing, intros, sickness, or injury. However, these are not the cause of aggression, genetics are. The rat was aggressive the whole time. If one thing didn’t trigger it, something else would, or it could show up without a trigger.
The Positive
The good thing is it can be bred out. A future without aggressive pet rats is possible. Ethical breeders do not breed aggressive rats. Pet stores, accidental litters, and backyard/ unethical breeders are where you will find aggression genes. It is possible to own rats without worrying about a bite.
Hidden Aggression
An ethical breeder can have or sell an aggressive rat without knowing. If you get an aggressive rat from a breeder who seems otherwise ethical, how they respond to being notified should reveal if they are. A breeder isn’t ethical if they blame you or call it normal. If they offer to take the rat back and discontinue or reevaluate the aggressive line, they are ethical.
Backyard breeders hide aggression by masking, or handling a rat 6 weeks or younger regularly. Handling unweaned rats does not help, unlike dogs where early handling is beneficial to development. Early handling hides a rat’s true temperament, which comes out after the rat leaves the breeder, perhaps during intros or getting a new home. Since most BYBs do not accept returns, the new owner is stuck with the aggressive rat. BYBs also rarely understand aggression. They may give advice to ‘train’ the rat to stop, endangering the owner and the rat’s cage mates by delaying proper action and spreading false information.
Other Signs of Rat Aggression
Biting is the black-and white of aggression, but there are other signs. Watch for excessive, persistent bullying. This behavior may lead to a bite. A rat ball, or an intense fight resembling a ball of rat, is aggression from the instigator. “No blood, no foul” does not apply. If you see these symptoms, separate the aggressor.
Not Rat Aggression
Things which are not aggression are bloodless nips, and predating other species. Rats eating another dead rat is not aggression, but an instinct to prevent attracting predators. They might groom you by nibbling on fingernails, toenails and pulling at our socks, bandaids, or dead skin. Rats also groom their cage mates. They might pull at stitches too, keep the rat away from those.
The Hard Truth
You can’t fix a rat with general aggression through training. We must isolate it from other rats to prevent injuries and deaths. They can cause permanent damage to anyone handling them or their cage while they are in it. Aggression’s unpredictable nature may surprise or make you think it happened once and will never happen again… Until it does. It could bite at any moment regardless of how careful anyone is. But if you read Rats 101: Essential Tips for New Rat Owners, you know keeping a rat alone causes depression and shortens lifespan.
A lonely rat has less desire to live than one with friends. Humans can’t replace other rats, and loneliness is worse than death. The kindest thing for a rat with general aggression is to put it down. It’s like genetic, non contagious rabies, which never goes away and creates chronic stress, keeping them from a good life. General aggression and its only solution is the saddest thing about rats. So, many people refuse to believe it. You formed a bond with them, there is no obvious physical ailment, and it’s hard to accept ending their life as the best option, but it is.
Bring it to a vet knowledgeable on the truth of general rat aggression for humane euthanization, or to an ethical breeder willing to take it for you. Believe me when I say I hate it as much as you do. But please, if you ever end up with an aggressive rat and can’t return it to the breeder, do what is best for them. Don’t make them suffer the rest of their life alone, afraid, and stressed.
References
APA References
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