Slender-billed Gull Larus genei

(last update: March 02, 2015)

Slender-billed Gull adult

Slender-billed Gull is a small to medium gull, only slightly larger than Black-headed Gull. In summer plumage, it lacks a dark hood on the head, but remarkably, as in Black-headed Gull, in winter it develops a dark patch on the ear-coverts (although much smaller). The most noticeable feature in Slender-billed Gull is the long neck, especially when alarmed. Furthermore, the head is elongated with a sloped forehead and the bill is particularly slender.

Slender-billed Gull breed commonly in isolated colonies in the Mediterranean and along the shores of Russian steppe lakes (e.g. Black Sea, Caspian Sea). It winters south along the west coast of Africa, the Mediterranean and to the east: the Arabian peninsular and western India. Most of the description below follows from P.J. Grant: “Gulls, a guide to identification”.

3CY & ADULT SLENDER-BILLED GULL

Next moult (to summer adult plumage) starts in February and ends in April. It’s a partial moult, including the body and head: the head becomes all white, sometimes with a pink hue. Adult birds develop a strong pinkish wash on the breast and belly.

From June into October the complete moult starts again with the inner primaries. When this moult is completed, Slender-billed is in so-called "adult winter" plumage. In general the colour of bare parts is somewhat duller and the head shows a small ear-spot on the rear ear-coverts.

Measurements in mm’s wing: 278-320, tail: 110-125, bill: 35-46, tarsus: 46-54; n = 24.