If the cygnets are very young and there has been a lot of rain, the parents may temporarily leave them on the banks to allow them to preen and dry. The cygnets do not have water repellent feathers yet, and by placing them on the bank, even if there is a lot of rain, the birds will not drown. If in the water, the young birds could drown because they can't float. The parents may feel very comfortable leaving the cygnets in your garden if they know there are no predators in the area.

However, if the parents leave them for long periods of time, i.e., more than 30-45 minutes, then you may want to contact Wendy Hermon at Swan Lifeline, Eton to check the family out and make sure everything is okay. The Regal Swan