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Location: Churchill, Manitoba, Canada

Also known as Pacific Diver.

Identification: Slightly smaller than Black-throated Diver with a finer bill but very similar. Adult breeding: closely resembles Black-throated Diver with white-chequered black back and dove-grey head but paler nape area more extensive and throat patch has purple (not green) iridescence. Adult non-breeding: dark-grey brown above clearly demarcted from white underparts as in Black-throated Diver but may lack conspicuous white flank patch seen on swimming birds.

Length 65-66cm. Wingspan 118cm.

Voice: Wailing, croaking and cackling calls.

Range: Breeds in north-eastern Siberia and in northern North America from Alaska east to Hudson Bay. Winters off Japan and on the Pacific coast of North America from Alaska to Baja California and in the commonly in the Gulf of California. May occur as a rare winter vagrant to the Atlantic coast but these birds may belong to Black-throated Diver G. arctica.

Habitat: Breeds on medium-large lakes and winters at sea.

Breeding: Breeds early-May to September, begins mid-June in north of range. Nests beside water often on an island or spit, a shallow scrape or more rarely a substantial mound of vegetation built in shallow water. Eggs: 2 (1 in replacement clutch), olive-brown, sometimes more greenish with sparse black blotches (76 x 47mm). Incubated by both sexes for 28-29 days. Young tended by both sexes, feed themselves at 35 days and fly at about 60 days

Diet: Fish, also molluscs and crustaceans.