Swans will both display before mating, then mate for life. They are devoted to each other, and remain together throughout the year. They keep their young with them until they nest again, some staying through a second clutch. If one of a pair of swans dies, the survivor usually takes a new mate, and they form a dedicated pair. Breeding
Swans usually mature in two to three years, and breed at around 3-4 years of age. The northern birds do not breed until their fifth or sixth year.
In their bulky nests, females do most of the egg incubation. The average clutch is about five eggs, but may be as many as ten. Incubation lasts about 30 days. Cygnets first learn to float in the water, then start to fly in about 60-75 days. Swans molt in July and August, when their cygnets are too young to fly.
Canon 50D, 150-500mm F5-6.3 APO DG OS