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

(last update: 2-2-2011)

Avi Meir (Israel)
Mars Muusse (the Netherlands)

Sooty Gull L. hemprichii near-adult, March 04 2002, visitor's centre of Nabq National Park, SE Sinai, Egypt.

As is the case with White-eyed Gulls, some near-adult Sooty Gulls may be difficult to age, more over since 3rd winter Sooty Gulls resemble 2nd winters, where 3rd winter White-eyed Gulls resemble adults. The second generation tail-feathers show various amount of black in second winter, normally creating a broken tail-band of sub-terminal markings, but as can be seen in the picture, black is limited to only a very small black mark near the shaft of the outer rectrices. The black primaries show white tips up to p8. Second winter Sooty Gull show white tips already, like many medium-sized gulls do, e.g. Common Gull (L. canus).
The complete moult to winter plumage takes place between probably August and May, a wide range depending on the geographical location of the breeding population and subsequent hatching of the eggs. This results in various stages of wear in the wing-coverts (and other feathers of course). The partial spring moult takes place between March and October.
Note the stronger, straight, two-toned bill. It has a yellowish base and a black band. The ill-defined crescent is much less obvious than similar aged White-eyed Gulls. Note the lack of any blackish feathers on the head and neck, which are typical for White-eyed Gull. The legs are yellowish green.

Sooty Gull has rounded and broader wings compared to White-eyed Gull, and a more swinging flight-impression, unlike the stiff flight of White-eyed Gull. In flight the stronger neck and breast are obvious, creating a profile more in line with white-headed gulls from the Western Palearctic. Note the obvious white trailing edge in Sooty, which is much thinner in White-eyed Gull.