(2061) Larus ridibundus.
THE BLACK-HEADED GULL.
Larus ridibundus Linn., Syst. Nat., 12th ed., i, p. 255 (1766); Blanf. & Oates, iv. p. 300.
Vernacular names. Dhomra (Hind.).
Description. Whole head and neck chocolate-brown, deepening to almost black on the hind-neck and below the throat; a ring or. white feathers round the eye ; back, scapulars, lesser and median wing-coverts and inner secondaries pearl-grey ; rump, upper tail-coverts and tail white; outer greater coverts and primary coverts white : first primary white with black tip and black edges to both webs ; second and third with less black on the outer web : fourth white on the outer web, grey on the inner, black-tipped ; remaining primaries and outer secondaries white, the primaries tipped with black and edged terminally on the inner web with black, this gradually lessening until the innermost is all grey, or nearly so ; in freshly-moulted plumage most of the inner primaries have small white tips ; under plumage white.
Colours of soft parts. Iris dark brown or crimson-brown; bill and legs deep bright red.
Measurements. " Wing 295 to 315 mm. (one 320), 285 to 302 mm.; tail 110 to 125 mm.; tarsus 43 to 49 mm.; culmen, 31 to 36 mm., 29 to 33 mm." (Witherby).
In Winter plumage the dark brown head disappears, though a few feathers show dark here and there in many specimens.
Young birds are brown above, the feathers edged with pale grey ; tail white with a broad subapical band of blackish-brown. Specimens occur in every phase of intermediate plumage.
Nestling in down. Buff or brownish-buff, darkest above, palest below ; head, back and throat streaked with dark brown.
Distribution. Breeding throughout temperate Europe and Asia from the Faroes to Kamschatka; in Winter South to North Africa, India, China and Japan and also to the Philippines and Malay Peninsula.
Nidification. The Black-headed, or Laughing, Gull breeds from the middle of April, or earlier to the middle of May but, in places where they are much harassed, they will continue laying until June and I have seen fresh eggs in July. It nests in colonies, often of great size, numbering many hundreds or even thousands, on sand-hills, marshes, inland lakes and locks and occasionally on heather-covered dry hills. The nest varies from a scratching in the sand lined with a few scraps of grass to a well-made massive affair of weeds, grass and rubbish. The normal clutch of eggs is three but two often and four occasionally are laid. The colour varies greatly. Most eggs have the ground-colour ranging from pale yellow-stone, grey-green, olive-green, buff, olive-brown or brown to warm rich shades of the same. The markings are generally blotches and spots of dark brown with others underlying of violet and grey. Intruders to the breeding-grounds are greeted with a babel of sounds and as each nest is approached the birds which own them swoop down at them with harsh croaks. Jourdain gives the average of one hundred eggs as 51.9 x 37.2 mm.
Habits. This is a Gull which is often found inland as well as on the coast and it lives largely on worms and inserts, following the plough for this purpose. They also eat all sorts of grain, shoots of some crops, seed, beetles, slugs, snails as well as small fish, sand-eels etc., the young being fed almost entirely on these latter. They sometimes also become great thieves of young birds and eggs of other birds. Their two most often used notes are a harsh " gek, gek " and a loud wailing " ka-yek, ka-yek " but they have many other harsh calls and cries. This Gull is resident in most places but wanders far in the Winter and is then not very rare in India, especially on the North-West coast.