Black-throated Diver

Seen one? Add it to your free UK BirdedexHear its song and see the mapFree, no app download. Rare bird: +8 points when you log it.

Black-throated Diver in the UK

A rare breeding bird and scarce winter visitor. The last full survey, in 2006, found about 215 pairs, all in Scotland and up 16% on the 1994 count. Around 560 birds winter around the UK coast. It is on the Amber list and is protected under Schedule 1, so it is an offence to disturb birds at or near a nest. Nests sit at the water's edge and are easily flooded or disturbed, and floating nest rafts on some lochs have improved breeding success.

Where and when to see a Black-throated Diver

Breeding birds are on large freshwater lochs in the north-west Highlands and the Outer Hebrides from April to August. Watch only from public roads and lay-bys with a telescope, and never approach a bird or an island. From October to March look in sheltered sandy bays. The bays of south Cornwall are a regular wintering area, and birds also occur off north-west Scotland and along the North Sea coast. Calm days make birds far easier to pick out.

Habitat, diet and field notes

Habitat: Highland lochs (summer).
Diet: Fish.
Field note: Striking velvet-grey nape.

How to identify a Black-throated Diver

Between Red-throated and Great Northern Diver in size. In summer the head and hind neck are soft grey, the throat is black, the neck sides have fine black-and-white stripes, and the back carries blocks of white chequers. In winter it is black above and white below with a sharp, straight border down the neck. The dark cap comes down to the eye. Look for a white patch on the rear flank at the waterline. The bill is straight, dagger-shaped and held level.

Call and song

On breeding lochs it gives a loud, mournful wail that rises in the middle, heard mostly at dawn and dusk, and a croaking flight call. It is silent in winter. Heard something you cannot place? Bird Hear identifies UK birds from a 10 second recording, free in your browser.

Confusion species

• Red-throated Diver: Red-throated is smaller and paler with a thin bill tilted upwards, and in winter white surrounds the eye.
• Great Northern Diver: Great Northern is bulkier with a heavy bill, a steep forehead and, in winter, a dark half-collar and pale eye-ring.
• Pacific Diver: Pacific Diver, a rare vagrant, lacks the white rear flank patch and often shows a thin dark strap under the chin.

Related guide Bird migration in Britain.

Conservation status and Birdedex points

In the Birdedex the Black-throated Diver is a Rare tier bird, worth +8 points when you log one. It is Amber-listed in Birds of Conservation Concern 5, the middle level of concern in the UK. It is protected under Schedule 1 of the Wildlife and Countryside Act 1981, so it is an offence to disturb it at or near the nest. We blur the location of every sighting of this species.

Recent UK sightings

Similar birds

• Red-throated DiverUncommon · Lochs (summer); coast (winter)
• White-billed DiverRare · Coastal seas (vagrant)
• Pacific DiverLegendary · Coastal seas (very rare)
• Great Northern DiverUncommon · Coastal seas (winter)
• Slavonian GrebeRare · Highland lochs (summer)
• OspreyRare · Lochs

Black-throated Diver: quick answers

Where can I see a Black-throated Diver in the UK?

In winter, scan sheltered bays in Cornwall, north-west Scotland and along the east coast from a headland or harbour wall. In summer, birds can be seen from roadsides beside the larger lochs of Wester Ross and Sutherland. Keep your distance in the breeding season.

What does a Black-throated Diver eat?

Fish, caught on dives that usually last well under a minute. On breeding lochs it takes trout, char and other small fish, and adults may fly to other lochs or the sea to feed. In winter it eats small sea fish and some crustaceans.

Is the Black-throated Diver rare in the UK?

Yes. With about 215 pairs it is one of our scarcer breeding birds, and the winter population is only a few hundred. Many suitable lochs are unoccupied, so the low numbers are linked to breeding success more than to a lack of habitat.

Kit that helps

Bird ID starter kit. Affiliate links, our own picks, no extra cost to you.