On our golf course we have a pair of swans. Two years ago the male swan drowned all 7 cygnets ( R.S.P.C.A. confirmed this.) Our greenkeeper had checked on them all at 7am and by 8am when he went back, all the cygnets were dead. The female swan left the male swan on his own, and he has been on his own for over 12months.( all last year).
This year, and we assume it is the same male swan,(greenkeeper said he is sure it is the same one) he has a partner. They have nested and have had 7 cygnets. The cygnets were about 3 weeks old, Monday last week we discovered 4 dead cygnets not far from the nesting site. By Sunday the other 3 cygnets have dissapeared.
He is very teritorial and aggresive to other swans, we have numerous ponds on our course but he does not allow any other swans to reside there, he has not allowed any other birds apart from moor hens and ducks on his lake.
Is it possible that we have a rogue swan that will always kill his young? If not what can be the reason for his behaviour.
It is heartbreaking to see. What can we do?