First and foremost, do any of the pairs have cygnets? If you place any swans with cygnets onto a lake with other swans, there is a possibility of a fight taking place. This is the same thing during mating and nesting season. The pairs may get along quite well until breeding season when the hormone levels rise and then it becomes a free for all.

If there are no cygnets, open the indoor pens and stay close to prevent any aggression. Provide a community food bowl and some lettuce or other treats like bread. Observe how the swans interact. Make sure that everyone gets the same amount of food and treats and you do not show partiality toward any swan so they all remain equal in your treatment. This is extremely important because in nature, the alpha bird/animal will eat first, etc. However, your job is to control this in the introduction stage so that hopefully, the alpha behavior will not lead to overaggression.

If after several hours or days, no aggression, then you should be safe to send them out onto the pond. If there is a minor fight, you need to check to see that there are no visible bloody wounds, etc. Again, usually, the swans will get along but there will and can be an occasional territorial war which is normal in nature. If there are signs of over aggression in the indoor pen or on the pond, then as normal as this may be, you may need to rethink introducing everyone so that you do not incur unnecessary veterinarian medical bills. But, we would suggest the open introduction as a means to introduce everyone and ascertain if the mutual pond sharing will work. During nesting/mating season, we would advise you to separate them until the hormones settle. The Regal Swan