Nest Building: Once the pair has bonded, they start constructing a nest. Both the cob and the pen contribute to building the nest, which can be quite large and made of materials like grass, reeds, and twigs. The nest is typically placed near the water, such as in a marsh or along the shore of a lake or pond.
Mating: During the breeding season, which usually occurs in the spring or early summer, the male initiates mating by mounting the female while both swans are in the water. The male will extend his long neck to reach and insert his bill into the female's cloaca, which is a combined opening for the reproductive, urinary, and digestive tracts. This position allows the male to transfer his sperm into the female's reproductive system.
Egg-laying and Incubation: After successful mating, the female swan lays eggs, typically between three and eight eggs per clutch. Both the cob and the pen take turns incubating the eggs, with the male primarily handling nighttime incubation and the female incubating during the day. The incubation period for swan eggs is generally around four to six weeks.
Parenting and Raising Cygnets: Once the eggs hatch, the newly emerged cygnets (baby swans) are cared for by both parents. The cygnets are precocial, meaning they can swim, feed, and walk shortly after hatching. The parents protect and guide their cygnets, teaching them how to feed and survive on their own. The family group, which is referred to as a "herd" or a "bevy," remains together for several months, up to a year, before the young swans become independent.