Chroicocephalus

Chroicocephalus
	Black-headed gull (Chroicocephalus ridibundus)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Laridae
Genus:	Chroicocephalus; Eyton, 1836
Type species
	Larus capistratus Temminck, 1820 = Larus ridibundus Linnaeus, 1766;
Species
	See list

Chroicocephalus is a genus of medium to relatively small gulls which were included in the genus Larus until genetic evidence published in 2005 showed that Larus as then constituted was paraphyletic. Ten species are currently accepted. The genus name Chroicocephalus is from Ancient Greek khroizo, "to colour", and kephale, "head".

Taxonomy

The species now placed in this genus were formerly assigned to the genus Larus. A molecular phylogenetic study published in 2005 found that Larus, as then constituted, was paraphyletic.^[1] In the resulting rearrangement to create monophyletic genera, the genus Chroicocephalus with resurrected to contain a clade of species, all of which have black heads.^[2] The genus Chroicocephalus had been introduced in 1836 by the English naturalist Thomas Campbell Eyton. Although he listed two species in the new genus, he did not specify a type.^[3] In 1840 George Gray designated the type as Larus capistratus which had been described by Coenraad Jacob Temminck in 1820.^[4] This taxa is now considered to be a junior synonym of Larus ridibundus, the black-headed gull, that had been named in 1766 by Carl Linnaeus.^[5] The genus name Chroicocephalus combines the Ancient Greek χρωικος/khrōikos meaning "coloured" with -κεφαλος /-kephalos meaning "-headed".^[6]

Saunders's gull was formerly included in this genus until a 2022 study demonstrated that although it occupied a basal position in the genus, it was not closely related to the other members. It is now placed in its own genus Saundersilarus.^[2]^[7]

Description

The species range from 28 cm up to 48 cm long, with Bonaparte's gull being the smallest, and Andean gull the largest. In all species, the body and tail are white, and the upperwing pale grey; the wingtips have distinct grey, white, and black patterns important for identification. Several have distinctively brown, pale grey, or blackish-grey coloured heads in the breeding season, but some also have the head pure white like the rest of the body. The eyes are dark in some species, or with a distinctive white iris in others; the legs and bills are bright to very dark red.^[8]

Representatives of this genus are found in regions/subregions all over the world, except for Antarctica; the species are often parapatric, but with two species together in New Zealand, the Mediterranean region, parts of southern Africa, and parts of South America. Exceptionally, three species (black-headed, brown-headed, and slender-billed gulls) can occur together in parts of southwest Asia.^[8]

Species

The genus contains ten species.^[2]

Common Name	Scientific name	Breeding range
Slender-billed gull	Chroicocephalus genei	south Iberian Peninsula, south Europe, Black and Caspian Seas and Turkey to Central Asia, Pakistan and coastal far northwest India; Mauritania, Senegal and Gambia
Bonaparte's gull	Chroicocephalus philadelphia	Boreal forest zone from southwest Alaska mainland and northwest, southwest Canada to east Quebec
Silver gull	Chroicocephalus novaehollandiae	Inland south Australia and coastal throughout Australia; coastal New Zealand and outlying islands and New Caledonia
Black-billed gull	Chroicocephalus bulleri	Mostly on braided rivers, North and South Islands of New Zealand
Andean gull	Chroicocephalus serranus	Andes of far southwest Colombia to south central Chile and southwest Argentina
Brown-hooded gull	Chroicocephalus maculipennis	Inland and coastal southeast Brazil, central Chile, north central Argentina and Falkland Islands
Black-headed gull	Chroicocephalus ridibundus	Coastal far south Greenland, inland Iceland, temperate and subarctic west Europe across Russia to Yakutsk region, Kamchatka Peninsula, Sakhalin (east Russia); in south through Caspian Sea, north Central Asia, north, central Mongolia and northeast China; also west central Newfoundland
Brown-headed gull	Chroicocephalus brunnicephalus	Inland Tibetan Plateau of Tajikistan, Xinjiang (west China), Ladakh (far northwest India) and Tibet
Grey-headed gull	Chroicocephalus cirrocephalus	Coastal and inland Africa south of the Sahara and Madagascar; coastal Ecuador and Peru; south Uruguay and northeast Argentina to Santa Fe, Argentina
Hartlaub's gull	Chroicocephalus hartlaubii	Coastal central Namibia to Western Cape, south Africa

Fossils

Huahine gull †Chroicocephalus utunui -French Polynesia.

References

^ Pons, J.-M.; Hassanin, A.; Crochet, P.-A. (2005). "Phylogenetic relationships within the Laridae (Charadriiformes: Aves) inferred from mitochondrial markers". Molecular Phylogenetics and Evolution. 37 (3): 686–699. doi:10.1016/j.ympev.2005.05.011.
^ ^a ^b ^c Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (February 2025). "Noddies, skimmers, gulls, terns, skuas, auks". IOC World Bird List Version 15.1. International Ornithologists' Union. Retrieved 5 June 2025.
^ Eyton, Thomas Campbell (1836). A History of the Rarer British Birds. London: Longman, Rees, Orme, Brown, Green, and Longman. p. 58. The pagination restarts for the second half of the book with the title A Catalogue of British Birds. This arrangement is indicated in the table of contents at the beginning of the first half of the book. The list of species placed in Chroicocephalus begins on page 53 of the Catalogue.
^ Gray, George Robert (1840). A List of the Genera of Birds : with an Indication of the Typical Species of Each Genus. London: R. and J.E. Taylor. p. 79.
^ Dickinson, E.C.; Remsen, J.V. Jr., eds. (2013). The Howard & Moore Complete Checklist of the Birds of the World. Vol. 1: Non-passerines (4th ed.). Eastbourne, UK: Aves Press. p. 225. ISBN 978-0-9568611-0-8.
^ Jobling, James A. "Chroicocephalus". The Key to Scientific Names. Cornell Lab of Ornithology. Retrieved 4 June 2025.
^ Černý, David; Natale, Rossy (2022). "Comprehensive taxon sampling and vetted fossils help clarify the time tree of shorebirds (Aves, Charadriiformes)" (PDF). Molecular Phylogenetics and Evolution. 177: 107620. doi:10.1016/j.ympev.2022.107620.
^ ^a ^b Hoyo, Josep del (2020). All the birds of the world. Barcelona: Lynx edicions. ISBN 978-84-16728-37-4.

[1] Pons, J.-M.; Hassanin, A.; Crochet, P.-A. (2005). "Phylogenetic relationships within the Laridae (Charadriiformes: Aves) inferred from mitochondrial markers". Molecular Phylogenetics and Evolution. 37 (3): 686–699. doi:10.1016/j.ympev.2005.05.011.

[ioc-2] Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (February 2025). "Noddies, skimmers, gulls, terns, skuas, auks". IOC World Bird List Version 15.1. International Ornithologists' Union. Retrieved 5 June 2025.

[3] Eyton, Thomas Campbell (1836). A History of the Rarer British Birds. London: Longman, Rees, Orme, Brown, Green, and Longman. p. 58. The pagination restarts for the second half of the book with the title A Catalogue of British Birds. This arrangement is indicated in the table of contents at the beginning of the first half of the book. The list of species placed in Chroicocephalus begins on page 53 of the Catalogue.

[4] Gray, George Robert (1840). A List of the Genera of Birds : with an Indication of the Typical Species of Each Genus. London: R. and J.E. Taylor. p. 79.

[5] Dickinson, E.C.; Remsen, J.V. Jr., eds. (2013). The Howard & Moore Complete Checklist of the Birds of the World. Vol. 1: Non-passerines (4th ed.). Eastbourne, UK: Aves Press. p. 225. ISBN 978-0-9568611-0-8.

[6] Jobling, James A. "Chroicocephalus". The Key to Scientific Names. Cornell Lab of Ornithology. Retrieved 4 June 2025.

[7] Černý, David; Natale, Rossy (2022). "Comprehensive taxon sampling and vetted fossils help clarify the time tree of shorebirds (Aves, Charadriiformes)" (PDF). Molecular Phylogenetics and Evolution. 177: 107620. doi:10.1016/j.ympev.2022.107620.

[Hoyo-8] Hoyo, Josep del (2020). All the birds of the world. Barcelona: Lynx edicions. ISBN 978-84-16728-37-4.

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v t e Gulls (subfamily: Larinae)
Genus	Species († indicates a species confirmed to be extinct)
Larus	Pacific gull Belcher's gull Olrog's gull Black-tailed gull Heermann's gull Common gull Short-billed gull Ring-billed gull California gull Great black-backed gull Kelp gull (or Cape gull) Glaucous-winged gull Western gull Yellow-footed gull Glaucous gull Iceland gull Thayer's gull European herring gull American herring gull Yellow-legged gull Caspian gull Vega gull (or East Siberian gull) Mongolian gull Armenian gull Slaty-backed gull Lesser black-backed gull Heuglin's gull
Ichthyaetus	White-eyed gull Sooty gull Great black-headed gull (or Pallas's gull) Audouin's gull Mediterranean gull Relict gull
Leucophaeus	Dolphin gull Laughing gull Franklin's gull Lava gull Grey gull
Chroicocephalus	Silver gull Red-billed gull Huahine gull † Hartlaub's gull Brown-hooded gull Grey-headed gull (or grey-hooded gull) Andean gull Black-billed gull Brown-headed gull Black-headed gull Slender-billed gull Bonaparte's gull Saunders's gull
Hydrocoloeus	Little gull
Rhodostethia	Ross's gull
Rissa	Black-legged kittiwake Red-legged kittiwake
Pagophila	Ivory gull
Xema	Sabine's gull
Creagrus	Swallow-tailed gull
Gull eggs as food Hybridisation in gulls