Mute swan nest

Mute swan nest

Observation - Mute swan nest - UK and Ireland. Description: We have been watching one of the swans sitting on this nest for some weeks now. Each year, the swans on our local lake successfully raise six of seven cygnets, so we were surprised to see only one cygnet this year. It looks as though the eggs didn't hatch

We have been watching one of the swans sitting on this nest for some weeks now. Each year, the swans on our local lake successfully raise six of seven cygnets, so we were surprised to see only one cygnet this year. It looks as though the eggs didn't hatch. The swans do return to the nest, but only occasionally - they seem to have given up on these eggs. I'm surprised they haven't been cracked open by a heron, crow or rat. One possibility may be that local wildlife wardens have pricked the eggs to keep the population down. I've heard they do that with the Canada geese some years, but I'm not sure they'd do that with swan eggs - or even be able to get past two fierce swans in order to do it.
I've uploaded a picture of one of the swans. I'm pretty sure it's a mute swan, but I've added it here so people can check