Hartlaub's gull | |
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Adult, Cape Town | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Laridae |
Genus: | Chroicocephalus |
Species: | C. hartlaubii |
Binomial name | |
Chroicocephalus hartlaubii (Bruch, 1855) | |
Synonyms | |
Larus hartlaubii |
Hartlaub's gull (Chroicocephalus hartlaubii) is a small gull in the genus Chroicocephalus . [1] It was formerly (as with other related gulls) placed in the genus Larus until genetic research demonstrated that the old broad view of that genus was paraphyletic. [2] [3] In the past it had sometimes been treated as a subspecies of the Australasian silver gull (C. novaehollandiae), [4] but is now treated as a separate species; [5] current genetic evidence suggests its closest relative is not the silver gull but the African and South American grey-headed gull (C. cirrocephalus), [3] and in particular the African subspecies of it C. c. poiocephalus (with the possibility that C. cirrocephalus is paraphyletic with respect to C. hartlaubii: Černý & Natale 2022, Fig. 6). [6]
The species' name commemorates the German physician and zoologist, Gustav Hartlaub. [7] In the past, it was also sometimes known as "king gull". [8]
Hartlaub's gull is 37–39 cm in length, with a wingspan of 89–92 cm and a weight of 235–340 g. It is a mainly white gull with a grey back and upperwings, black wingtips with conspicuous white "mirrors", and a dark red bill and legs. When breeding it has a very faint lavender grey hood, but otherwise has a plain white head. The sexes are similar. This species differs from the slightly larger grey-headed gull in its thinner, darker bill, deeper red legs, paler, plainer head, and dark eyes. It takes two years to reach maturity. Juvenile birds have a brown band across the wings. They differ from same-age grey-headed gulls in that they lack a black terminal tail band, less dark areas in the wings, darker legs, and a white head. [5] [9]
The gull is a non-migratory breeding resident endemic to the Atlantic Ocean coastline of South Africa and Namibia. Although it is predominantly coastal or estuarine, it is not a pelagic species, and is rarely seen at sea far from land. About one half of the total population, currently estimated at 30,000 birds, lives within the Greater Cape Town area. It has accommodated well to humans, and can become very tame around habitations. Although it is a relatively rare species, about the tenth rarest of the world's 50 or so gull species, it is common in its range and is widely regarded in Cape Town as a nuisance, fouling buildings and bathing in urban ponds. It has, at times, been a hazard to aircraft near airports.
Like most gulls, Hartlaub's is highly gregarious in winter, both when feeding or in evening roosts. This is a noisy species, especially at colonies. The call is a raucous crow-like kaaarrh. This species is frequently the subject of complaints about the noise it makes in urban areas.
Hartlaub's gull breeds in large colonies, and the main traditional breeding colony for the Cape Town area is on Robben Island. The adults fly to the mainland to find food for their chicks, a round trip of about 24 km. Although most breed in large colonies on islands, some have started nesting on coastal buildings. [9]
The species is omnivorous like most Larus gulls, and they will scavenge at tips and feed on scraps as well as seeking suitable small prey, often by wading in shallow water.
Charadriiformes is a diverse order of small to medium-large birds. It includes about 390 species and has members in all parts of the world. Most charadriiform birds live near water and eat invertebrates or other small animals; however, some are pelagic (seabirds), others frequent deserts, and a few are found in dense forest. Members of this group can also collectively be referred to as shorebirds.
Gulls, or colloquially seagulls, are seabirds of the subfamily Larinae. They are most closely related to terns and skimmers, distantly related to auks, and even more distantly related to waders. Until the 21st century, most gulls were placed in the genus Larus, but that arrangement is now considered polyphyletic, leading to the resurrection of several genera. An older name for gulls is mews; this still exists in certain regional English dialects and is cognate with German Möwe, Danish måge, Swedish mås, Dutch meeuw, Norwegian måke/måse, and French mouette.
Terns are seabirds in the family Laridae, subfamily Sterninae, that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated in eleven genera in a subgroup of the family Laridae, which also includes several genera of gulls and the skimmers (Rynchops). They are slender, lightly built birds with long, forked tails, narrow wings, long bills, and relatively short legs. Most species are pale grey above and white below with a contrasting black cap to the head, but the marsh terns, the black-bellied tern, the Inca tern, and some noddies have dark body plumage for at least part of the year. The sexes are identical in appearance, but young birds are readily distinguishable from adults. Terns have a non-breeding plumage, which usually involves a white forehead and much-reduced black cap.
Laridae is a family of seabirds in the order Charadriiformes that includes the gulls, terns, noddies, skimmers, and white terns. It includes around 100 species arranged into 22 genera. They are an adaptable group of mostly aerial birds found worldwide.
The black-headed gull is a small gull that breeds in much of the Palearctic in Europe and Asia, and also locally in smaller numbers in coastal eastern Canada. Most of the population is migratory and winters further south, but many also remain in the milder areas of northwestern Europe. It was formerly sometimes cited as "common black-headed gull" to distinguish it from "great black-headed gull".
The laughing gull is a medium-sized gull of North and South America. Named for its laugh-like call, it is an opportunistic omnivore and scavenger. It breeds in large colonies mostly along the Atlantic coast of North America, the Caribbean, and northern South America. The two subspecies are L. a. megalopterus — which can be seen from southeast Canada down to Central America — and L. a. atricilla, which appears from the West Indies to the Venezuelan islands. The laughing gull was long placed in the genus Larus until its present placement in Leucophaeus.
Bonaparte's gull is a member of the gull family Laridae found mainly in northern North America. At 28 to 38 cm in length, it is one of the smallest species of gull. Its plumage is mainly white with grey upperparts. During breeding season, Bonaparte's gull gains a slaty-black hood. The sexes are similar in appearance.
Pallas's gull, also known as the great black-headed gull, is a large bird species. As is the case with many gulls, it has traditionally been placed in the genus Larus. The scientific name is from Ancient Greek. Ichthyaetus is from ikhthus, "fish", and aetos, "eagle".
The yellow-legged gull is a large gull found in Europe, the Middle East and North Africa, which has only recently achieved wide recognition as a distinct species. It was formerly treated as a subspecies of either the Caspian gull L. cachinnans, or more broadly as a subspecies of the herring gull L. argentatus. The genus name is from Latin Larus which appears to have referred to a gull or other large seabird, and the species name honours the German zoologist Karl Michahelles.
The red-billed gull, also known as tarāpunga and as the mackerel gull, is a native seagull of New Zealand, being found throughout the country and on outlying islands including the Chatham Islands and subantarctic islands. It was formerly considered a separate species but is now usually treated as a subspecies of the silver gull.
The brown-headed gull is a small gull which breeds in the high plateaus of central Asia from Tajikistan to Ordos in Inner Mongolia. It is migratory, wintering on the coasts and large inland lakes of the Indian Subcontinent. As is the case with many gulls, was traditionally placed in the genus Larus.
The grey-headed gull, also known as the grey-hooded gull, is a small species of gull which breeds patchily in South America and Africa south of the Sahara. It is not truly migratory, but is more widespread in winter. This species has occurred as a rare vagrant to North America, Italy and Spain. As is the case with many gulls, it has traditionally been placed in the genus Larus.
The silver gull is a gull in Oceania. It is the most common gull of Australia. It has been found throughout the continent, but particularly at or near coastal areas. It is smaller than the Pacific gull, which also lives in Australia.
The lava gull, also known as the dusky gull, is a medium-sized gull and a member of the "hooded gull" group. It is most closely related to the Laughing gull and Franklin's gull and is the rarest gull in the world. It is endemic to the Galapagos Islands.
The brown-hooded gull is a species of gull found in Argentina, Brazil, Chile, the Falkland Islands, and Uruguay. Its specific epithet, maculipennis, means 'spotted wings'. It is a white bird with a brown head and red beak and feet.
Saunders's gull or Chinese black-headed gull, is a species of gull in the family Laridae. It is found in China, Japan, North Korea, South Korea, Macau, Russia, Taiwan, and Vietnam. Its natural habitats are estuarine waters and intertidal marshes. As with many other gulls, it has traditionally been placed in the genus Larus, but based on phylogenetic work some have moved it to Chroicocephalus, while others argue it is sufficiently distinct for placement in the monotypic Saundersilarus. In 2023, this transfer was accepted by the International Ornithologists' Union.
The Andean gull is a species in subfamily Larinae of the family Laridae, the gulls, terns, and skimmers. It is found in Argentina, Bolivia, Chile, Colombia, Ecuador, and Peru.
The black-naped tern is an oceanic tern mostly found in tropical and subtropical areas of the Indian Ocean and western Pacific Ocean. They are rarely found inland. It was described from the islands around Sumatra. It is most closely related to roseate tern S. dougallii and white-fronted tern S. striata.
Chroicocephalus is a genus of medium to relatively small gulls which were included in the genus Larus until recently. Some authorities also include the Saunders's gull in Chroicocephalus. The genus name Chroicocephalus is from Ancient Greek khroizo, "to colour", and kephale, "head".
Cabot's tern is a species of bird in subfamily Sterninae of the family Laridae, the gulls, terns, and skimmers. It is found in the eastern U.S. and Middle America, the Caribbean, Trinidad and Tobago, and in every mainland South American country except Bolivia and Paraguay.