Biology

During the winter the white-headed duck forms large flocks which feed together on insect larvae and submerged plant material and seeds. They dive continuously, staying underwater for around forty seconds at a time. In late winter they moult and are rendered flightless. Once re-feathered they begin the migration to their breeding grounds in late February (6). At the breeding grounds they break up into small groups to find suitable nesting sites (7). The white-headed duck is polygamous and nests in reed beds, sometimes on top of abandoned coot (Fulica atra) nests. Between four and nine eggs are laid and incubated for 22 to 24 days. Eight to nine weeks after hatching, the young fledge (5). Unusually for ducks, the adults moult twice each year, once in winter and again after breeding. Once this is complete, both young and adults migrate back to the wintering grounds (7).