THE BLACK-HEADED GULL 



the pairing and nesting period. This Gull is eminently 

 gregarious, not only during winter, but in summer. 

 It begins to gather at the breeding-stations reed-fringed 

 pools and swampy meres in March, and in April nest- 

 building commences. The nests are mostly made on 

 the wet ground amongst the tufts of rushes and sedge ; 

 but sometimes the low trees and bushes are occupied. 

 In some cases the nests are little more than hollows in 

 the ground or tufts of herbage ; in others they are 

 compactly made of reeds, flags and coarse grass, often 

 increased in bulk to protect them from being washed 

 away. The three, or more rarely four, eggs diffe*" in 

 colour to an astonishing extent, but are usually of some 

 shade of brown or green in ground, marked in a variety 

 of ways with brown and grey of many shades. In some 

 places the birds are very carefully protected and the 

 eggs systematically gathered for culinary purposes. At 

 all times a gullery of this species is a remarkably pretty 

 sight, but when the birds are disturbed the air becomes 

 filled with clamouring hosts, the whole scene best being 

 likened to a dense snowstorm, in which each flake is an 

 anxious, protesting, fluttering, noisy bird. But one 

 brood is reared, and as soon as the young are sufficiently 

 matured the old wandering life along the coasts and 

 tidal rivers is resumed. 



The adult Black-headed Gull in winter plumage has 

 the hind head marked a little with grey, a dark spot in 

 front of the eye, another larger one on the ear-coverts, 

 the mantle, scapulars, innermost secondaries, and wing- 

 coverts delicate grey, the primaries white tipped with 

 black and the longest'margined with black ; the remainder 

 of the plumage white. Bill crimson ; tarsi, toes, and 

 webs crimson ; irides brown. Length 16% inches. 

 Early in spring even in January, but more usually 

 in February and March the adult assumes a dark 

 smoke-brown hood or mask, the feathers changing colour 



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