Guinea pigs are social animals that do not like to be alone. They enjoy companionship and social interaction with other guinea pigs. In larger groups, they feel safer and therefore happier. Guinea pigs living in groups are more confident, more susceptible to mental stimulation, have a more diverse diet, and are generally healthier. Guinea pigs raised alone are usually more stressed, less active, vocal, and more susceptible to illness. Interaction with your guinea pigs is very important, but no human interaction or caring can replace bonding with their own species. We recommend always having at least two guinea pigs in a home so that they have a companion.
Guinea pigs need time to adapt to new things and can be very territorial of their space. Patience and gradual progress is a must for successful pairing. The first step is to isolate the new guinea pig till you are sure that it is not sick or pregnant. If you really can not isolate them, ask your veterinarian to conduct a full health check on your new guinea pig. Do not place your new guinea pig into the same hutch with your old guinea pig right away.
2. Establishing Dominance
Try to pair the dominant guinea pig with a younger and more passive guinea pig. If you don't know what their personality is like, an older and younger guinea pig is a good start. Physically larger and smaller guinea pigs are also a way to go. They usually establish a natural hierarchy, younger guinea pig to an older one. Note that you should not have a very feisty younger guinea pig with a more laid back older guinea pig. In this case, the young one may challenge the older alpha guinea pig’s position.
If you have a male, it's better to have another male. If you have a female, you will want to pair it with another female. This is the easiest way to go because it does not require neuter or spay surgery. If you happen to have a female and male in the same cage, they could start breeding very quickly. Guinea pigs can sometimes hide pregnancy really well, so be aware.
Find a neutral space like outside in a contained area or a spare room for them to meet for the first time. Make sure the hutch or cage is large enough so that they have somewhere to escape from if they feel overwhelmed. The minimum size is 120cm x 50cm x 50cm for two guinea pigs living together but providing the most space possible is ideal for the first meeting. Choose a quiet, enclosed and spacious space that makes both feel safe. Block all interfering factors, such as loud TV, children or other pets. Do not try to force the guinea pigs together. Give them time to build confidence and become comfortable enough to be close to each other. Providing a plentiful amount of fresh veggies can alleviate any worries and help them stick together, be sure to supervise them in case a fight starts. They may start to connect with each other by receiving treats.
5. Clean Cage
If you are adding a new guinea pig to the existing hutch where the old guinea pig lived, make sure you clean the hutch completely and rearrange it so that the two guinea pigs will feel like the hutch is neutral territory. A tip would be to gently rub the hay from the old cage to the new guinea pig’s temporary space so he/she smells more like other piggies before joining.
Make sure you make time to monitor their behaviors and constantly look for positive and negative behaviors. Some positive behaviors would be grooming each other, lying next to each other and sharing food and water. Expect to see some concerning behaviors at first. Concerning behaviors to watch out for are constant teeth chattering, biting, hiding from each other and chasing. Some concerning behaviors are expected in the beginning but if your piggie shows aggression and looks stressed out, end the session and try it again the next day.
Introducing new guinea pigs into a home can always be stressful for both you and your piggies. However, be patient with them because in the end, your piggies will be happier with a companion to live with.