How To Introduce Two Pet Rabbits
Rabbits are social but territorial creatures. While they enjoy companionship, they have to take time to get to know their new housemates or they will fight. It is best to introduce rabbits to each other while both are still young, less than four months old, but you can introduce them later if you are careful. Make sure both rabbits are either neutered or spayed to lessen the chance of fighting between them. Once you have the rabbits neutered or spayed, introduce them to their new surroundings first. Put them in a cage and let them get used to the sights and smells of their new home, let them get used to you, and then introduce them to each other in a neutral place that is clear of toys or other objects belonging to either rabbit. This prevents territorial battles over what belongs to whom. Place one rabbit in the neutral area, such as a bathroom, and enter holding the other. Allow them to see each other and touch noses, then place the second rabbit in the neutral area and let them interact. Watch for signs of aggression, separate them at the first indication of hostility, and reintroduce them later on.More info here: Rommerz Rabbit Hopping Competition in Germany