Unfortunately, unless the cygnets are reunited and stay with the mother swan, their chances for survival are not very good. The cygnets must have their parent swan for at least 4-6 months so that they have protection against predators and learn how to be a swan. The mother swan may be a new mother and not know how or where to build a nest protected from the weir or how to look after such young offspring.

If the mother swan was still worrying about the remaining cygnet, she may not have flown to the other cygnets which she might have normally done and led them to a safer area from the other swans.

Thank you for trying to save the family, but this is an extremely difficult case to keep the cygnets from falling over a weir and getting separated unless the parent and cygnets are moved upstream a significant distance from the weir or downstream away from the other swans. The Regal Swan