- Lifespan
- 12–17 years in the wild
- Size & Weight
- 40–47 cm, wingspan 67–73 cm; 600–850 g
- Habitat
- Freshwater lakes, reservoirs, gravel pits, and coastal waters with good diving depths and aquatic vegetation.
- UK Distribution
- Widespread across the UK, with resident populations year-round. Numbers increase significantly in winter with continental migrants arriving from September to March.
- Diet
- Diving duck that feeds primarily on aquatic invertebrates, especially chironomid larvae and freshwater snails; also takes aquatic plants and seeds.
- Prey
- Aquatic insect larvae (particularly midges), crustaceans, molluscs, small fish and plant material
- Predators
- Pike, cormorants, and occasionally raptors such as golden eagles and sea eagles; gulls and corvids may take eggs and ducklings.
- Mating Season
- September to April, with peak activity in autumn and winter
- Breeding
- Clutch of 6–14 eggs, incubation period 23–28 days, single brood per season. Nests in dense vegetation near water.
- Behaviour
- Highly gregarious, often forming large flocks, especially in winter. Excellent divers that can reach depths of 3–10 metres. Males produce distinctive head-throwing displays and whistle calls during courtship.