Rats enjoy communal living but care needs to be taken when introducing them to either a single rat or to a group of rats (a mischief). Here are some simple tips to follow:

  • Young rats of at least six weeks of age are the easiest to introduce and waiting until 7-8 weeks when they are more robust is even better. Much younger and they may be killed by the dominant rat, although adult rats can also be hard to introduce.
  • At around 13-14 weeks male rats develop more adult characteristics and scent changes so introducing these older rats can be more problematic. At around 6-12 months, hormone levels peak in the males and they may have a greater tendency to dominance and aggression.
  • Female pet rats tend to be more accommodating towards each other and other males.

How to introduce a rat to a group…

The worse way to introduce rats is to give one access to an existing rat’s cage. The resident rat is likely to defend its territory and it doesn’t lay the groundwork for future harmonious relations. So, the first big requirement is to buy a new cage. The rat cages can then be kept in sniffing (but not biting) distance.

There is no set time frame for how long the two cages should be kept close together – sometimes it can be days or weeks before the rats show a non-aggressive interest in each other. Signs to look out for and that indicate aggression are the fur being fluffed up, wagging the tail from side to side and approaching the other rat side on. If you are NOT seeing those signs it can be a sign that they are ready to be introduced.

rat cage

Harmonious living

  • Swap bedding from one cage to another so each learns the other rat’s
  • Locations can be swapped – putting the rat in their fellow rat’s cage and vice versa – and can also start off the socialisation process.
  • The next physical introduction should be on neutral territory where the resident rat is also unfamiliar with the environment – this could be in another new (or unfamiliar and fully cleaned with odour removing spray) cage or even a bathtub.
  • Some rat keepers also put a little bit of vanilla extract on each rat to mask their individual scents and make them appear more alike.
  • Have a water spray and a thick towel to rescue the situation in case a fight breaks out.
  • Hand feeding both rats treats at this point can also be a useful way to bring them physically closer together and create rewarding experiences.
  • Once they are in their new shared home, additional toys and hammocks can be added to the cage as the rats gain in confidence and there are fewer concerns about them being cornered. To start with though, the environment should be kept fairly neutral.

In groups of rats, once a rat is accepted by the dominant rat, any further scuffles tend to be mild. Rat behaviour can be complex and variable though. A rescue rat that has been brought up alone can find it difficult to communicate and may need a much longer introduction. Some rats that are territorial can also be happier in a smaller, simpler space with less to defend. It means there is no ‘one cage fits all’ approach to rat housing.

group of rats