Introducing New Rats | Lurelin Rats

Introducing Rats - The Carrier Method

While one introduction technique won't suit all rats, the carrier method is by far the easiest to make sense of and follow with a great success rate. It works well as the small initial space means that rats work out their hierarchy faster and there is a reduced chance of injury (injuries mainly occur when a rat is running away). This means that their overall stress levels should be lower and for a shorter period of time. When done correctly, it does not result in flooding/learned helplessness. The information below tends to focus on worst-case scenarios (arguing/altercations etc), but generally speaking intros tend to be quite smooth with only a few initial minor arguments.

You should introduce the rats to each other once the new additions have undergone a quarantine period, ideally in a separate airspace (different building), for 2 weeks. If this is not possible, try to source your rats from reputable sources to minimise risk and do the best quarantine that you are able to do (different room, good hygiene, etc). If you are introducing kittens to adults, ensure that the kittens are at least roughly half/two-thirds the size of the adults so that they are able to defend themselves if needed and they are less "fragile". This is usually when they are 9-11 weeks old. Do not rely on the age of the rats for introductions, as there have been cases of backyard breeders lying about ages and rats from some lines grow more slowly than others. Kitten-adult intros are the easiest, though kittens start to be recognised as adults by other rats at ~12 weeks so intros should start before this point.

You should not introduce rats who are ill and weak, as this puts them at risk and they may not be able to defend themselves should they need to. Do not intro during a heatwave due to the risk of overheating either. If an individual has known, unresolved hormonally-driven aggression issues, neuter them before attempting intros.

You will need:

- A carrier, such as the Ferplast Aladino

- A hospital cage, such as a second-hand hamster cage like the Pets at Home XL. If you have a large group, you may need to start at this point to have enough space for everyone. There should be enough space to allow all of the rats to completely lay down plus a little bit extra.

- A hamster cage, such as an Alaska (optional, but may be helpful if you have a tricky group or you want to stagger things more)

- Your full set-up and a way to divide it if it is large like the Little Zoo Venturer

- A thick towel if you are concerned that there may be arguments needing breaking up (the towel is to protect your hand/help remove the problem rat)

There are some basic principles when doing the carrier method:

1. Deep cleaning each space.

2. Waiting for positive behaviours (sleeping in one pile, positive grooming behaviours, not defending items, and relaxation around each other). A rat pile does not necessarily mean that a group is ready to move up to the next stage! Avoidance, general defensiveness and arguments (not to be confused with altercations) are not positive behaviours and should be worked through before moving up a stage.

3. Adding in items, including potential snagging points such as more enclosed spaces like double hammocks.

4. Waiting for positive behaviours again.

5. Moving up a stage.

And some general "rules":

1. Start intros when you have plenty of time to be near your rats. For example, if you work Monday - Friday, start intros as soon as you get home on Friday and stay up a bit later, or start first thing on Saturday morning.

2. Once together, do not separate the rats unless there has been an altercation and you need to put a complete stop to intros.

3. Disrupt any arguing (side shuffling, brief rat balls). Warning signs include fluffed up fur and side shuffling towards another rat. You can sometimes ease initial tensions by gently swinging the carrier or walking around with them. You can disrupt arguing with a weird noise, talking firmly, a quick blow of air onto the rat, tapping/running nails on the bars, gently swinging or carrying them around in the cage, or a sharp tap on the cage. Avoid yelling and banging on the cage repeatedly as this can wind aggravated rats up further. If this happens repeatedly or cannot be interrupted, remove the upset rat(s) and firmly stroke them for a little while. Driving is often suggested to help, however I don't recommend this as it becomes unsafe if they're arguing or having an altercation and you can't pull over!

4. Do not free roam the rats until they have been settled in the final stage for a good length of time (usually at least ~1 week).

5. Do not give the rats treats until they are interacting positively at their given stage.

6. Scatter feed their food so that they don't resource guard.

7. Easier said than done, but stay calm! If you're anxious, your rats will pick up on that.

8. There is no prescribed timeframe within which intros should occur. Go by when the rats are ready.

9. If arguments persist at one stage, consider moving back a stage.

THE CARRIER METHOD:

PART A: The carrier

Clean your carrier thoroughly then add a layer of substrate. Put all of the rats into the carrier. Observe their behaviour. If you see any negative behaviours (such as puffed-up fur, side shuffling, or brief rat balling), distract the rats. If they continue despite the distraction, remove them for a breather. If negative behaviours persist, consider whether you need to approach introductions from another angle (eg. intro a couple of rats at a time rather than all at once), or if the aggressor requires neutering. If they're obsessing over you and wanting attention, take a step back so you can still observe them but aren't as close.

Once the rats are sleeping in a pile together and are interacting with each other positively, move up to the next stage. If they are sleeping separately, pick up the carrier and move it somewhere else, or gently swing it and put it back down to encourage them to interact.

Example: here are my does during intros in late 2022. Notice how in the left photo the bottom middle rat is fluffed up. She later got into a brief rat ball with another rat. I tapped on the side of the cage to defuse the situation. When it happened again soon after, I distracted them again, took her out and firmly stroked her until she calmed down, then put her back in.

Within a couple of hours, they had settled in a pile together. I had put an old hammock over the top of the carrier so that they weren't distracted by me.

PART B: The hospital cage

Thoroughly clean the hospital cage and add a layer of litter if you intend on litter training the lazy way. If not, just use substrate. Leave the rest of the cage empty bar a couple of water bottles.

Once again, observe their behaviour and let them work through minor disputes while distracting them if things escalate. Scatter feed their mix to ensure that they can forage together. Make sure that each individual is spending time with every single other rat. If you spot two rats that don't quite get along like the others do, hang fire and wait for them to figure things out.

Once they're settled and interacting in a positive way (not avoiding each other and generally relaxed), add in a single hammock and a ledge. Then a toy. Then a double hammock. Work up to a mini cage set up. See if they can share a wet meal in a large bowl nicely.

For me, this stage is the most important one. If you can work through potential snagging points here and add toys, double hammocks etc, your chances of success in the later stages are much improved. By the end of this point, each rat should be interacting positively with every single other rat within the group, and they should be intermingled. They should be able to share items and food and show signs of being a cohesive group.

Part C: The hamster/small cage (optional, but a good idea)

Most of the hard work should be done now! But if your group has been a bit touchy, moving to a hamster cage such as an Alaska or small cage such as a ferplast can help to bridge the gap before going into the main cage.

Put the rats back into the carrier and transfer the substrate from the hamster cage into the next stage after deep cleaning it. Transfer the water bottles. Leave it otherwise empty. Add the rats back in.

Do the same as before, where you add in a single hammock once they're interacting positively, then work up to a double hammock, rope/tie holder and toys. By the end you should have added all of the fallbreakers you intend on using for the next stage. Ensure that they can share sleeping areas, more enclosed spaces, their dinner and a wet meal in this space and that they are each interacting well with every single other rat. Then get ready to move up again.

Part D: Full small cage/half big cage

By now you should know the drill! Empty and deep clean your small cage (eg. Coco Large or Mamble) or half your big cage (eg. Little Zoo Venturer, Pet Planet). Add in a couple of fall breakers (ideally the ones you managed to use in the previous stage) and pop them in.

Once again, add items when you see positive behaviours, and eventually introduce more enclosed spaces. Eventually you'll have a full (or full half) set up. If you're at your final cage, you're all done! If you have a larger cage, move them up to the whole set-up next time you clean out in about a week unless they need to stay at this stage for longer.

If you've been litter training, now is the point to only have your litter in the litter trays and use normal substrate.

Part E: Full cage and free roam

By now they should be a pretty cohesive group. Once they're fine in the full set-up, free roam in a more open space, then add more enclosed items as time goes on. I usually wait a week or two before free roaming again depending on the individuals involved.