Black Tern
Chlidonias niger
Overview
The Black Tern is a marsh tern — unlike the sea terns, it feeds by dipping gracefully to the surface of water for insects rather than plunge diving. Extinct as a UK breeder (it bred on fens until the 19th century), it passes through in small numbers on migration. In spring, adults are coal-black with grey wings. In autumn they're white below with dark patches on the head and breast-sides. Marshside is the best site on the Sefton Coast.
At a Glance
| Order | Charadriiformes |
| Family | Laridae |
| Habitat | Freshwater lagoon · Coastal marsh · Open water |
| Diet | Insects, small fish — dips to the surface rather than plunging |
| UK population | Passage only; extinct as breeder in the UK — bred on marshes until 19th century |
| Sefton Coast | Irregular passage visitor to Marshside; most often seen in small numbers in late August |
| Conservation | UK Amber List |
Where to See It
Marshside RSPB main lagoon on passage. Buoyant, tern-like flight over water.
Identification
Small tern. Spring adult: dark grey-black body, grey wings, white under-tail. Autumn adult/juvenile: white below with dark 'shoulder' patches and dark cap/ear-spot. Buoyant, light flight, dipping to water surface.
Viewing & Photography Tips
Visit Marshside in late August after westerly weather. Look for small terns flying low over the lagoon with a buoyant, dipping action — quite different from the plunge-diving Common and Sandwich Terns.
Conservation Status
UK Amber List
This species is on the UK Amber List for Birds (BoCC5), indicating moderate concern. Population monitoring and habitat management remain important for its continued recovery.
Frequently Asked Questions
Why did Black Terns stop breeding in the UK?
Black Terns bred on the fenlands of East Anglia until the 19th century but were lost as a breeding species through the drainage of their marsh habitat. Attempts to re-establish breeding — including creation of floating nest rafts — have had limited success. They are now purely passage visitors to the UK.
Related Species
Plan your visit to the Sefton Coast
Marshside RSPB, Formby pinewoods, Ainsdale NNR — practical guides to getting there, what to bring, and the best spots for each season.