If the swans are wild, then there is not much you can do. If they are captive (pinioned and unable to fly) the only thing you can do is place them in a pen (enclosed top to bottom so that predators cannot climb over or dig under the pen to access the swans). The pen should be 1/2 on the bank and 1/2 in water with a feeder inside. The outside perimeter of the pen should have poultry fencing from the bottom rail up to approximately 4 feet around so that the cygnets cannot crawl through and the predators cannot reach in. The pen should have not abrasive substrate (flooring) or steep banks as this can cause severe injuries to the feet or legs which can be detrimental to the health of the swans, including death.

Straw should be placed in the pen to allow the swans to build a nest and begin laying eggs. The entire family should be kept in the pen for approximately 3-4 months. This may be an extreme amount of time, but will allow the cygnets to get large enough to keep smaller predators, i.e., large fish and turtles from attacking. Now, having said all of this, there are no guarantees that the cygnets will still survive or that the parents will nest in a pen. But, this is the only viable way to keep the family from predators. The Regal Swan