Degus fight. Its used to establish dominance, set the social hierarchy, and express dislike. This behaviour is normal among all species, and is present in the cage as much as it would be in the wild, possibly even more as their is less territory to control and more (sexual) frustration. On 99% of occasions you should do nothing and leave them to it, as interfering would only harm proceedings and cause more fighting. It is only when things get serious you should break them apart. Degus will tend to fight more during the breeding season, which is winter-spring time, as the breeding hormones cause a greater need for dominance.
Most fighting will be non-serious, where they are establishing the social hierarchy by displaying dominant behaviour over each other. This can include chasing each other around the cage, squeaking at each other, mounting each other so the one below becomes submissive and the one on top dominant, and standing on the hind legs and 'boxing'. This is normal behaviour and nothing to worry about, and you should not intervene as it will only set them back a stage and make them fight more. These fights are fought in a way as to not cause injury, just a bit of friendly rough and tumble. Fighting can also occur when there are limited resources to share such as food and treats, with Degus showing such behaviour as turning their backs, blocking access to the food bowls and treats, and loud squeaking to warn them away, so great care must be taken to ensure everything is equal and is placed far enough apart for the Degus to see there are 2 (or more) separate areas without coming into too much contact with each other. Put simply, place the food bowls around 10cm apart.
You should only step in and separate them when there is biting and lunging at each other which causes wounds, and when they become locked in a ball rolling around. This is serious fighting, and can cause injury, as both Degus are unwilling to back down and fight to the death. Any injuries sustained during these fights should be checked by a Vet, including any observable changes in behaviour or discomfort. Remember, a Degu can not speak and tell you they need treatment, so it is up to you as a good owner to ensure their health and well-being takes priority. If you do need to separate them, it may be hard to introduce them back together, and may need to be kept separate for a few weeks before being able to be reunited. Our new introductions guide gives some tips on how to re-introduce our pets, including ensuring the cage is neutral (fully cleaned so it does not smell of one Degu more than another) and the Degus first reunion is in a neutral setting where they can be monitored without escape (such as a dry bath tub).
Preventing Degus from Fighting
A lot of serious fighting can be avoided by following a few basic steps:
- Have separate food bowls for each Degu, placed suitably apart
- Have plenty of shelters to provide hiding places for one to run to instead of being forced into a fight
- If you give one Degu a treat, give the others a treat
- Have a spare cage (I use the one I place my pets in whilst cleaning the main cage) ready for if the worse happens
- Treat each pet equal, do not favour and treat one more over the other