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Slender-billed gull | Chroicocephalus genei
Dunbekmeeuw | Gaviota picofina
An elegant gull of salt pans and coastal lagoons, long-necked, small-headed and long-billed — looking less like a black-headed gull than like something halfway to a tern. Its stronghold is the western Mediterranean: anyone looking for it in the Ebro delta, the salt pans of Alicante or the Odiel marshes will find it without leaving Spain. In north-west Europe, such as the Netherlands, it is a genuine rarity: eight accepted records in a little over twenty years, all in spring, mostly adults and not infrequently two or three together.
Voice
A hoarse, nasal call recalling black-headed gull but fuller and lower. At the colony adults give long series of six to ten hard kraah notes closed off by a higher krerr. Over a salt pan the effect is a continuous din from dozens of birds, louder than a black-headed gull colony of the same size.
No freely licensed recording is available for this species yet.
Identification
Bigger and longer than a black-headed gull, with a long, gently drooping bill that reads black at range and dark red up close. The head is small and rounded with a high forehead running smoothly into the bill base; neck and legs are long, so a swimming bird sits high and stretched. The head stays white all year with no hood, the iris is pale yellowish-white and the eyelid ring a thin red line. Mantle pale grey, underparts white with a rosy flush that can be strong in spring. In flight a white primary wedge as in black-headed gull, tipped black.
Confusion species
Black-headed gull is the bird to work against. Slender-billed shows a longer, evenly drooping bill without the angled gonys, a small round head with a high forehead, and noticeably longer neck and legs. In summer plumage it lacks the chocolate hood altogether, keeping at most a dusky smudge behind the eye, and the breast carries a pink flush that Black-headed rarely matches. The pale iris against Black-headed's dark eye settles most birds at close range.
Habitat
Salt pans, coastal lagoons, river mouths and the shallow inshore water in front of them. Breeds colonially on bare sand and shell islets with sparse halophytic vegetation, usually alongside terns, avocets and other gulls. Feeds by walking and picking over mud and by flying low over shallow water, dropping from about a metre to seize fish, shrimps and insects.
Where the bird is most at home, classified with EUNIS — the European standard for habitats.
Range and movements
Scattered colonies around the Mediterranean, the Black Sea and the Caspian, east to Kazakhstan and north-west India, and along the coasts of Mauritania and Senegal, as well as in Asia Minor and the Middle East. Spain holds the western stronghold: the species breeds regularly in the Ebro delta, the Santa Pola and La Mata-Torrevieja salt pans and the Albufera of Valencia, and in Andalusia at Punta Entinas-Sabinar, Doñana and the Odiel marshes, with the wetlands of the Guadalquivir estuary as a link between them; part of the population stays near the colonies in winter, the rest spreads to other coasts. North of the Pyrenees it is a rare visitor: in north-western Europe, including the Netherlands, recorded only in spring and always in small numbers.
- Resident
- Breeding (summer)
- Winter
- Passage
- dark = core range, pale = thinly spread
How and when to look
In north-west Europe this is a bird you wait for rather than look for. To see it reliably, work the Ebro delta or the Santa Pola salt pans in April or May, scanning from the dyke tracks; at the Odiel marshes it pays to walk the paths between the pools early in the day, while the light is still low and the pink on the breast shows well. Pick out the shape first if in doubt: the long neck and drooping bill carry further than any plumage detail.
Conservation status
Not globally threatened, but the European population is small and concentrated at few sites, which makes it vulnerable to changes at any one of them. The Spanish population is growing and passed 2,500 pairs in the 2020 census. The main pressures are altered water management in working and abandoned salt pans, generalist predators reaching the nesting islets, and disturbance, since a colony that flushes does not always settle again.
Scientific name
Chroicocephalus genei | (di Brème, 1839)
Di Brème described the species in 1839 as Larus genei; because it was later moved to another genus, the author and year stand in brackets. The genus Chroicocephalus was introduced in 1836 by Eyton. Chroicocephalus combines the Ancient Greek khrōikos 'coloured' with -kephalos '-headed'. genei honours the Italian naturalist Giuseppe Gené. The specimen the first description was based on came from Sardinia.