- Lifespan
- 15–20 years in the wild, with some individuals recorded living over 25 years
- Size & Weight
- 70–100 cm long, wingspan 121–149 cm; 2.0–3.5 kg
- Habitat
- Coastal waters, estuaries, large inland lakes, and reservoirs where fish are abundant.
- UK Distribution
- Found around all UK coasts and major inland waterways; resident year-round with populations augmented by continental migrants in winter, particularly from November to March.
- Diet
- Almost exclusively fish, including sea bass, flatfish, eels, trout, pike, and perch, consuming 300–400 g daily.
- Prey
- Fish species including sea bass, mullet, flatfish, eels, trout, pike, dace, and perch
- Predators
- Chicks and eggs vulnerable to gulls, corvids, and foxes; adults have few natural predators but are occasionally taken by white-tailed eagles.
- Mating Season
- March to July, with peak breeding April to May
- Breeding
- Clutch of 3–4 eggs, incubation period 28–31 days, fledging at 48–50 days; typically one brood per year, though re-laying occurs after egg loss.
- Behaviour
- Highly gregarious, roosting and breeding in colonies that can exceed 1,000 birds. Expert divers capable of reaching depths of 9 metres, they pursue fish underwater with remarkable agility. Often seen perched with wings spread to dry their feathers, a behaviour reflecting their wettable plumage.