"My Rats are fighting!"

What to do when rats argue

One of the most frequent questions I get from rat owners is, “My rats are fighting, what do I do?”

This comes from people all over the world, messaging me on TikTok, Instagram, or any other way they can find me. It’s not uncommon, but even so there is nothing more disturbing to an owner than rats that don’t get along.

Rats are a gregarious species and our domestic rats display even more social behaviour than wild rats¹. Social contact is so important for pet rats that many scientists are now saying that even in laboratories, contact between rats should only be denied in exceptional circumstances.² And it’s not only the rat’s immediate happiness that is at stake. Studies in which juvenile rats have been isolated, preventing them from vital social development, show that such aloneness has knock on effects on how the rats navigate the world through adulthood.³

Rats are contact animals with complex social bonds. Some breeders claim that their own rats, derived over generations, tend not to fight, while outsiders coming into the rattery may prove different. Though not proven, it is possible that pet rats can detect related animals. After all, rats produce over twenty different pheromones and, in the wild, rats detect family members quite quickly.⁴ Having said that, pet rats generally do get along, even if they are from different family groups, and domestic Norway rats are far less aggressive than their wild counterparts. And fighting rats are performing a behaviour that both takes up energy and risks injury. But the fact remains that sometimes rats fight and, if there are arguments, what do we do?

Rats are contact animals

The answer depends on the particulars of the situation. Facebook rat groups warn rat owners about the stress that lone rats suffer, and they do this for a good reason: largely speaking, rats should always be housed in groups as part of the necessary enrichment that is part of a high quality of life. A small group of three is all you need to fulfil the social needs of your pets and keeping rats in groups will not diminish their interest in you. But rats being kept in groups only reduces stress if the groups are harmonious and stable.⁵ Being caged with a rival, may result in far more stress to your rat and, indeed, depression and death can occur in “omega” rats even if no physical fighting is observed.