The slender-billed gull (Larus genei) is most easily identified by its distinctive profile, with a long, sloping forehead and a long, slightly drooping beak, for which it is named (2) (3). The head, neck, rump and tail are white, while the back and the upper surfaces of the wings are grey, with a white leading edge to the wings and black tips to the outer primary feathers. The underparts are white, sometimes with a rosy tinge (2) (3). The slender-billed gull has long, blackish-red legs, a dark red beak, and yellowish-white eyes, with a red eye ring (2) (3). Outside the breeding season, the slender-billed gull sometimes has a small, dusky spot on the side of the head (2) (3).
The juvenile slender-billed gull has greyish markings on its head, and immature birds have darker markings on the wings and more pink-orange legs than the adults (2). This species can sometimes be confused with the black-headed gull (Larus ridibundus), but is distinguished by its more angular, sloping head, longer bill, white rather than black head during the breeding season, and slightly larger size (2) (3). The calls of the slender-billed gull include high, chattering notes and a nasal ‘yep, yep’ (3).
- Goéland railleur.
- Length: 42 - 44 cm (2)
- Wingspan: 102 - 110 cm (2)
- 220 - 350 g (2)