INTRODUCING A NEW PET RABBIT
Rabbits in the wild are territorial and have defined social groups. These characteristics are shared by pet rabbits, so introducing a new pet rabbit to a household with one or more established pet rabbits can be challenging, and can require an extended period of time.
Before beginning the process be sure all rabbits are healthy and, if recently neutered or spayed, that they are fully recovered from surgery.
Neutered male with spayed female is the pairing that seems to work best, but other combinations can work.
IN THE BEGINNING
The rabbits should be kept securely confined, but within sight and smell of each other. Bedding from the cages can be swapped regularly, so that the rabbits can get used to each other's smell within their own territory.
Keep the rabbits securely separated but feed them within sight of each other. Feeding is a very social activity for rabbits and eating with each other can help them get used to their new social grouping.
Only once the rabbits have shown an interest in each other through non-aggressive interaction, such as lying next to each other or sniffing each other, should they be introduced to each other without a barrier.
PUTTING THE RABBITS TOGETHER
The rabbits should be introduced on territory that is neutral for both of them, such as a room that neither rabbit has been in.
Scatter food around the neutral area. This will encourage them to forage, which is a common social behavior in the wild.
The introduction must be supervised, and the owner must be prepared to break up a fight. Rabbits in the middle of a fight will bite and scratch indiscriminately; they are as likely to injure the person who is trying to break up the fight as they are to injure each other. A heavy towel or blanket is a useful tool for safely breaking up a fight.
A 5- to 10- minute meeting is suitable for the first time. Some sniffing and chasing is acceptable, but the meeting must be stopped if fighting occurs. A good outcome is the rabbits lying down separately and ignoring each other.
Meetings can be continued daily for increasing lengths of time.
The rabbits can be put together in their original, "non-neutral" territories once they are grooming each other, lying down peacefully, and eating together. Once the rabbits are able to spend hours at a time in this situation then they can be allowed to share a sleeping area and live together.
Patience is important. If fighting occurs, the owner must go back to "IN THE BEGINNING", and start over. It is also important to understand that their are some pairs that will never bond, and there are some individual rabbits that need to live solitary lives.