Rats are extremely sociable and really thrive when they have the companionship of other rats. Lone rats crave this attention so will often become depressed or display aggressive or nervous behaviour.
Rats can be housed in pairs, although a trio or more will often live together more happily as they create their own social network. Pairs of rats can sometimes get agitated with one another and will tend to show dominant behaviour. Time spent out of the cage and fun training can help prevent this.
It’s usually best to keep rats in same-sex groups. However, males can be castrated so they can be mixed with females if they don’t bond well with other male rats. Females can also be neutered by experienced, rat-friendly vets if they are particularly tricky to mix.
Introducing your rats to each other
Always introduce rats on neutral territory that they don’t normally have access to – like a sofa, in the hallway or a small bathroom (but make sure the toilet seat is down!). This gives the rats time to establish a hierarchy with each other and to socialise without the stress of an enclosed environment.
Do this for the first three to seven days. If the initial encounters seem promising, you can then try to introduce the rats to each other in a spacious cage. The cage should be thoroughly cleaned so that it holds neither rat’s scent, and placed in an unfamiliar room to make sure it’s neutral territory.
Line it with a floor bedding such as shredded paper, scatter food in the bedding for them to mutually forage together and add one to two flat hammocks. Avoid adding too many objects initially, such as tunnels and houses, as this can affect how the rats bond. Medium-sized, flat hammocks are perfect as a resting place but avoid territory building.
Signs your rats accept each other:
Even if the signs are encouraging, keep a close eye on your rats until they have settled. This could take up to a week.
Signs your rats might not be suited:
If this kind of behaviour persists for more than an hour, separate the rats. Unfortunately, this particular mix is not likely to work.
Keep a close eye on your rats for the first two weeks
Health check each rat regularly throughout the first two weeks of introductions to monitor for any injuries. Fight wounds can get infected quite easily, and you may need to take your rats to your vet for a check-up.
Once you’re seeing positive signs, slowly introduce a new toy each week. Avoid sudden, sweeping changes to the environment – such as a complete change of toys or a thorough clean – during the first few weeks. This could provoke an unexpected argument and a breakdown of the bond.
Once the rats are happily bonded, continue adding toys and items that will make their environment more fun and rewarding.