- Lifespan
- 15–20 years in the wild
- Size & Weight
- 31–35 cm, wingspan 50–58 cm; 120–150 g
- Habitat
- Coastal islands and headlands with sparse vegetation, nesting on rocky or sandy substrates close to shallow coastal waters and productive fishing grounds.
- UK Distribution
- Rare summer breeding visitor to the UK, with small colonies on islands off Scotland, Northern Ireland, and occasionally southern England. Migratory, wintering in African waters.
- Diet
- Exclusively fish, primarily small species such as sand eels, sprats, and anchovies caught by plunge-diving.
- Prey
- Sand eels, sprats, anchovies, small herrings
- Predators
- Great Black-backed Gulls, Lesser Black-backed Gulls, corvids, foxes (at nesting sites), and occasionally peregrine falcons
- Mating Season
- May to August
- Breeding
- Clutch size 1–2 eggs; incubation period 21–26 days; fledging at 28–35 days; typically one brood per season.
- Behaviour
- Highly gregarious, breeding in small colonies and roosting communally. Males perform elaborate hovering and courtship displays with fish offerings. They are agile fliers with distinctive long tail streamers that enhance manoeuvrability during hunting.