Birds of Mongolia

ID The world’s smallest gull. In addition to size, adult is readily distinguished from other Mongolian gull species by black hood (in breeding plumage, vs. dark brown in Black-headed Gull); and, in flight, absence of any black on upperwings, and conspicuous blackish underwings with narrow white trailing edge. Juv and 1st-winter birds have striking black M-pattern spanning back and wings, similar only to immature Ross’s Gull and Black-legged Kittiwake (both rare vagrants), which both lack Little Gull’s dark crown patch and grey bar along trailing edge of secondaries in these plumages. Voice Tern-like, harsh keck or keck-keck-keck. Habitat Nests in reedbeds and on vegetated islands and shores of lakes and rivers, often in colonies of terns and other gull species. Behaviour Buoyant, agile and tern-like in flight; often catches insects in the air and picks food items from water’s surface. Status Very rare and local breeding visitor; known to nest at only a few locations on Lake Achit in Great Lakes Depression and at Lake Hövsgöl; also an uncommon passage migrant across northern Mongolia, late April to late August. Taxonomy Formerly placed in genus Larus.

ID Medium-sized, white-headed gull. All plumages are broadly similar to those of Mongolian Gull, but the latter is 25–30% larger with much longer, heavier and differently marked bill. Size similar to Relict Gull, with juv and 1st-winter birds closest in plumage details, but differences in head and bill shape and colour, and much more extensive brown streaking and speckling on head, breast and mantle distinguish Mew Gull. Greenish leg colour also diagnostic in adult and 2nd-winter birds. See also Black-legged Kittiwake. Voice Calls a mewing gya gya or gyu gyu, also drawn-out glyoooo. Habitat Lakes and rivers. Behaviour Gregarious, usually colonial, often nesting with other gulls on islands. Defers to larger gulls at feeding gatherings. Status Very rare and local breeding visitor to a few lakes in Great Lakes Depression and possibly in suitable habitat in Khangai and elsewhere in northern Mongolia; and uncommon passage migrant throughout the rest of the country apart from most arid southern deserts and mountains, late April to early September. [Alt: Common Gull]

ID An agile, medium-sized gull with tern-like flight. Breeding adult distinguished from other gulls by combination of slender unmarked greenish-yellow bill, short black legs and ‘ink-dipped’ wing-tips with no white ‘mirrors’. Non-breeding adult similar to breeding adult, but has dark grey bar on sides of head. In flight, juv and 1st-winter birds show bold black ‘M’ above, set off by clear grey mantle, black-tipped tail and white triangles in flight feathers; this pattern is superficially similar to Little Gull, but much ‘cleaner’. Compare also Ross’s Gull. Voice A high pitched tittering kitti-wake. Habitat Sea cliffs and open ocean; in Mongolia, lakes and other aquatic bodies. Behaviour Normally a highly pelagic gull, unlikely to linger long inland. Status Vagrant. One recorded in Herlen River, Töv province, on autumn migration (date unknown).

ID Breeding adult unmistakable with black neck-ring, rosy blush below and red legs, in addition to diminutive size. Imm and non-breeding adult have black eye patch, creating an odd ‘zombie’ look. In flight, superficially resembles Little Gull but adult has medium-grey, not blackish underwings; bold mantle pattern of juv and 1st-winter birds is much ‘cleaner’ than in Little; and tail is quite long and pointed, not notched as in Little. Compare also Black-legged Kittiwake. Voice Ku-wa ku-wa call occasionally given in flight. Habitat Nests in Arctic tundra and winters in Arctic Ocean. Behaviour Graceful and tern-like in flight. Often forages on mud like a wader. Status Vagrant. A single adult on Lake Uvs, Uvs province, 9 June 1977.

⇐

GULLS III

⇒