Once the cygnets begin to turn white, the parents no longer recognize them as offspring, but rather as rivals. The cygnet is probably a male and the oldest cygnet. Basically, the parents are telling the young swan to get lost prior to the next mating season. The rest of the cygnets will be getting this same treatment shortly.

If the cygnet is not an older bird, there is a possibility that there is something wrong with the cygnet, either it is sick or injured and the parents know it. The swan parents do not want the sick or injured bird hanging around the family as it could lead a predator to the family or if the bird is sick, a disease could kill the family and the rest of the flock.

If the chasing and nipping gets too aggressive, we would suggest that you contact the RSPCA or Swan Lifeline, Eton to have somewhat check out the situation and ensure that there is nothing wrong with the cygnet. The Regal Swan