There was a mute swan couple living in the canal in my neighbourhood. Last year, all their cygnets could not survive because they ate grass and could not digest.

This year, the mute swan couple change the location of the nest. The location can not be more worse and is next to bridge. And in the evening, teenagers gather there and throw broken bottles to the sitting female. I saw the broken bottle on the nest, while the female is gone.

I assume the mute swan couple separated due to failures of breeding offspring for twice. I heard that swans mate for life, which is not true. It is surprising to see that the male still stick around and try to incubate the eggs and sometimes he leave the nest to search food for more than 3 hours. Can the male succeed to hatch the eggs by himself.

How can I help if it is possible to increase the odds. I feel really sad because the family is broken by our human behavioural.