Guinea pigs are social pets and are therefore best kept in groups of two or more. This enables them to express their natural behaviour, and allows for all of their social needs to be met. However, when mixing unfamiliar individuals it’s important to consider their sex, age, size and personality in order to make it successful. Introducing them is also a gradual process, which should be done in various stages.
Successful pairings or groups
The most suitable pairings are two females or a neutered male and a female. If you would like to keep a group of three or more guinea pigs it’s not advisable to have more than one male as any more can cause a conflict over resources.
Neutering the male guinea pig removes the potential for any unwanted litters, and avoids the likely problems that can be caused by hormones. But it’s essential to wait four to six weeks after neutering before introducing a male guinea pig to any females as he might still be able to reproduce during this time.
Guinea pigs should not be kept with rabbits as they cannot communicate effectively with one another, and the guinea pig is at high risk of getting bullied by the rabbit.
Steps to take before introducing unfamiliar guinea pigs
- Make sure you know the sex of your guinea pigs – if you are unsure, contact your vet
- When you first get your guinea pigs home give them time to settle before starting introductions
- Ensure the hutch or cage is large enough – the minimum dimensions that Blue Cross recommends for two guinea pigs living together are 120cm x 50cmx 50cm, however you should provide the largest space possible
- Once settled, start to swap their items, such as bedding so they can become familiar with their new partner’s scent profile before meeting them. This is known as scent swapping and it’s important to watch for any adverse reactions your guinea pigs might have to the new smell being introduced.
- If the scent swapping goes well you can also try swapping their hutches and/or exercise runs so they can live or spend time in a space occupied by the other guinea pig
Introducing your guinea pigs
- If possible try to start by housing your guinea pigs with a mesh separating them so they can begin to communicate. You can place one in a run next to the other’s hutch, or two runs alongside each other.
- If the scent swapping and communication through the mesh looks positive the next step is to find a neutral space for them to meet in – an outside run is ideal, or a spare room
- If housing the guinea pigs next to one another hasn’t been possible before this stage we would recommend making a barrier in the neutral space that they can see and smell each other through. Remove it if positive behaviours are shown, such as sudden jumps (known as popcorning) and sniffing and spending time at the shared barrier.
- Provide items in the run such as open-ended boxes, open beds and tubes that the guinea pigs can hide in or behind, as this will ensure they have the space to move away and avoid the other individual should they feel the need to. Items that allow for a guinea pig to be cornered or become territorial, such as a carrier, shouldn’t be used.
- Scatter food and hay around so the guinea pigs have something to distract them. This also helps them to build a positive association with each other.
- Make sure you pick a time when you can sit and monitor their behaviour, and continue to look for the same positive behaviours you saw previously – as well as other signs such as grooming each other, lying next to one another and sharing resources; such as food or water
- Concerning behaviours to look out for are teeth chattering constantly, biting directed towards one another, constant hiding from one another, choosing not to spend any time together and chasing. You should expect to see some of these concerning behaviours to begin with, but if the guinea pigs look stressed or begin displaying aggression then end the session and try again the next day.
- Some guinea pigs will bond quickly, others may take longer and require further set ups like these to build a relationship
- Have a solid board handy that you can place in an emergency between the guinea pigs should they begin to display aggression
- End the session on a positive note if possible, or if you see concerning behaviour leading to stress or aggression from either guinea pig
- Several introductions set up in this way should build a relationship between the two and help get them ready to move in together
Moving your guinea pigs in together
- Before putting the new pair in their future home together remove any enclosed houses, such as carriers, and instead provide open objects to hide behind, such as tubes
- Scatter food around the hutch and provide two sources of water
- Monitor their behaviour in the hutch or cage initially, as a new environment can change the dynamics of a relationship
- But if you have no concerns based on your observations your guinea pigs are probably ready to start their life together
- If you do have any concerns, spend a few more sessions monitoring them in their home before leaving them alone together