You would need to first verify that the gender of all swans. Even one female will upset the status of your pond. The other swans know each other and have accepted them into the fold. Should you introduce a female and your swans are all males, there will be a fight for dominance and taking her on as a mate. This will mean that two swans will be left out causing stress from fighting, chasing, etc. Also, there are no guarantees that males will take another mate after losing their previous mate and may seriously injure or even kill the introduced swan.

Should you get an additional male, this will certainly upset the mix and fights resulting in possible injury and death to the swans could result.

So, this introduction will require that all swans are tested for gender. You will also need to build a pen (1/2 in water 1/2 on land with zero entrance (no steep or abrasive substrate) enclosed top to bottom so that predators cannot climb over or dig under to access the swan. You will need to have a feeder inside the pen so that the introduced swan can learn about you and how to feed. This introduction pen will also allow you to observe any signs of aggression on behalf of any of the swans (if so, then you will immediately know that you will need to find a safe good home for the new swan as this setting is not going to work out). The enclosure will also allow the new bird to learn about her new habitat, the other swans, you and recognize any predators in the area.

One last issue that you may have regarding the introduction of another swan (especially if it is an opposite gendered swan and capable of mating and producing offspring), you may need a possession permit for the swans and a breeding license should they breed and produce offspring. Many states including Indiana, are killing Mute Swans in order to introduce the larger Trumpeter Swans for Trophy Waterfowl hunting purposes. So, you may need to have these permits in order to introduce and maintain any swans. Furthermore, once the cygnets are approximately 8-10 months of age, the parent swans will begin to chase them from the area and you will need to find a new home for the young (again an almost impossibility with the state and federal Mute swan killing/control programs). You will also be responsible for having all cygnets pinioned (procedure that amputates a portion of one wing so that the swan can never fly) and it is must be conducted by a licensed veterinarian when the cygnets are 1-3 months of age. All veterinary care of the new swans will be your responsibility including any injury or illness care, vaccinations and you will need to provide paperwork regarding all of the veterinary care provided once you sell or give away the cygnets on a yearly basis. And, yes, Mute Swans have a brood of cygnets (1-8) on a yearly basis. This will be an inordinate amount of swans should you decide to get a female.

We would suggest that if you are not willing to seek permits or wish to have many cygnets on a yearly basis to maintain, that you not introduce another swan to the flock. The Regal Swan