Mute swans nest on large mounds that they build with waterside vegetation in shallow water on islands in the middle or at the very edge of a lake. They are monogamous and often reuse the same nest each year, restoring or rebuilding it as needed. Male and female swans share the care of the nest. Mute swans lay from four to ten eggs, and the female broods for around 36 days.
Adults of this large swan typically range from 140 to 160 cm long, although can range in extreme cases from 125 to 170 cm, with a 200 to 240 cm wingspan.