The two new swans are probably the same gender as the old white swan and when you got them they were juveniles and it was not nesting season. Now, nesting season presents a whole new ballgame in that this is the old swan's home and it feels threatened.

We would suggest not moving the old swan as this is its home and it will try to wander back. We would suggest that you take the two new swans and place them on your neighbor's lake. Life should return back to some normalcy. The black swan may be a different gender and the two swans have taken up house just because there is no one else on the pond of a different species and gender.

It will also be easier to catch the two swans on the land as opposed to catching the swan in the lake. If you choose to catch the old swan, you will need to use a kayak and try to funnel it into a pen or area in which you can surround and capture it. Finally, if you do capture the old swan, take it to a vet and get it sexed. Then, you might be able to introduce a swan of the opposite gender. However, generally, males after losing their mates will continue life just fine without trying to re-mate. If it is a female, she may look to re-mate. Let us know how this progresses. The Regal Swan