There will come a time in your rat-keeping life when you have two groups of rats that you wish to merge into one group of rats, or new kittens you wish to add to an existing group, or similar scenarios. There are many ways to introduce rats to other rats, and you can take as much time as you wish over it – complex scenarios of swapping cages over, neutral space time, back in their own cages, changing toys about between groups, or tiny carriers, then big carriers, then tiny cages, then medium cages, then big cages. They have their place, and I’m sure many rat owners love spending the time with complicated introductions, but this guide is for the lazy rat owner.
Introducing kittens to adults
To introduce kittens to adults, you will need a few simple items:
First, you will need an amount of common sense and knowledge of your own pets. Your adult group needs to be fairly stable and happy. Adding kittens to a group that is already stressed out (maybe someone needs castrated, or someone is ill and the rest are not happy about it, or the alpha or beta is rubbish at their job and leaving everyone else unhappy) will not make for a good outcome. If that’s your group – sort that out first before trying to add more rats.
Secondly, you need at least two appropriately aged kittens. Kittens for introducing to adults should be between about eight and twelve weeks old. Much younger kittens can be accidentally killed or injured by adults simply by accident, through normal introduction squabbles. Once they’re much older than that, the adults may see them as other adults and not give them the easy ride that babies enjoy.
Thirdly, you need an appropriately sized and furnished cage. Your triple royal suite, filled with tunnels and hidey holes, that is home to three residents and three new babies, isn’t going to be particularly useful here. Get a cage that suits the number of rats you’re introducing (so maybe half an SRS for six rats in total). Furnish it with no items where a rat can be trapped and be unable to run away – so hammocks are fine, ropes are fine, get rid of tunnels or closed off igloos.
Once you have found these ingredients, put ingredients one and two into ingredient three. Watch them. They’ll probably squabble a bit, and then they’ll stop, and then they’ll be pals. Watch them a bit more carefully for a couple of days to check they all seem fine (but remember they’re animals, not stuffed toys, and they may not instantly be best pals). Give them their tunnels back, and give them the rest of their cage back too.
Introducing adults to adults
To introduce adults to other adults, you’ll need at least two adult rats who don’t live together yet, an appropriately sized and furnished cage (see above), and a show tank or small carrier. Put the rats in the small tank or carrier. They’ll probably make the sort of noises you associate with rats having to work out who is the boss when they’re among strangers (if they get too noisy, I find tapping the top of the carrier and telling them to sort it out helps). Keep an eye on them, and they’ll probably stop after a while. Leave them in the carrier overnight, and in the morning when they’re all sleeping happily in a big pile, put them in an appropriate cage. After a few days, give them their stuff back.
I mean, use your common sense on this one too. If someone starts biting in the carrier and someone is bleeding, take them out. If a rat is obviously unhappy, stop the process. And remember that rats are living animals with their own preferences, their own personalities, their own likes and dislikes. Not all rats will get on, and if you find that introductions between specific rats are stretching on and on, and that they’re not getting on – it may be that they just don’t want to be friends. If you are continuing on with introductions when the rats have told you that they don’t want this, maybe it’s time to take a step back and decide if continuing on with the process is in their best interests.