White-eyed Gull (L. leucophthalmus) & Sooty Gull (L. hemprichii)

(last update: 24-1-2014)

Avi Meir (Israel)
Mars Muusse (the Netherlands)

White-eyed Gull L. leucophthalmus 3CY, February 20 2002, Shark Bay - Sharm El Sheik, S Sinai, Egypt.

Note the long, thin and slim bill, appearing all dark from a distance and clearly lacking the two-toned billed of Sooty Gull. White-eyed Gull is smaller in size and especially more elegantly build; lacking the high breast and strong neck of Sooty Gull. It has two white crescents in all plumages and especially the upper crescent is very obvious, while this is only a small crescent in Sooty Gull. The lower crescent is completely lacking in most Sooty Gulls.
In second winter, White-eyed Gull develops a blackish mask, extending on the ear-coverts. Second winter Sooty Gull is less contrastingly patterned on the head, more equally coloured brown and lacks the pure black feathers on the head in all plumages. White-eyed Gull appears more greyish on the upper-parts, where Sooty gull is brownish. By February (late winter) the bill colour is still the most obvious difference between White-eyed Gull and Sooty Gull: clearly two-toned in Sooty Gull and appearing all dark in White-eyed Gull (though with a slightly paler brownish base on the lower mandible). 
Second winter birds show more white in the tail than first winter birds (which have complete dark tails) and they often show a broken tail-band. Some feathers appear all white, some have a black basal centre. The amount of black may be related to timing of moult of a particular feather. Second winter birds resemble adults but lack the complete white tail and the hood is not fully developed, the chin and forehead still white or peppered.
The pointed juvenile primaries have been replaced for black second generation feathers with rounded tips. The tertials and wing-coverts have been moulted to plain grey feathers. The scapulars and mantle feathers generally have the same grey colour as the coverts but the upper scapulars show darker centres. The rump is dull grey, not clean white as in full adult plumage. The breast-band is not plain grey but has some maculation on the throat, side-neck extending to the nape. The legs are dull yellow.