Dolphin gull | |
---|---|
In Beagle Channel, Argentina | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Laridae |
Genus: | Leucophaeus |
Species: | L. scoresbii |
Binomial name | |
Leucophaeus scoresbii (Traill, 1823) | |
Synonyms | |
Larus scoresbii, Gabianus scoresbii |
The dolphin gull (Leucophaeus scoresbii), sometimes erroneously called the red-billed gull (a somewhat similar but unrelated species from New Zealand), is a gull native to southern Chile and Argentina, and the Falkland Islands. It is a coastal bird inhabiting rocky, muddy and sandy shores and is often found around seabird colonies. They have greyish feathers, and the feathers on their wings are a darker shade. Dolphin gulls have a varied diet, eating many things ranging from mussels to carrion.
The modern scientific name Leucophaeus scoresbii, together with the obsolete common name Scoresby's gull, commemorates the English explorer William Scoresby (1789–1857). [2]
The dolphin gull is found round the coasts of Chile, Argentina and the Falkland Islands. It is a vagrant to South Georgia and the South Sandwich Islands. It is found on rocky coasts and in the vicinity of other colonies of seabirds, slaughterhouses, sewage outflows and farmyards. [1]
The dolphin gull is a scavenger and opportunistic predator. It feeds on carrion, offal, bird eggs, nestlings, marine invertebrates and other natural food. When humans disturb nesting seabirds, it takes advantage of the absence of adult birds to raid their vacated nests. It was found that excluding humans from areas where cormorants were nesting increased the reproductive success of the cormorants. [3] It also takes advantage of the activities of marine mammals to scavenge for dead fish, placentae and faeces, which are a major attraction. [1]
Dolphin gulls nest in small colonies of up to 200 pairs and are usually on low cliffs, sand or shingle beaches, headlands or marshy depressions. Two to three eggs are laid in December and the chicks fledge in March. The older chicks gather together in crèches.[ citation needed ]
The dolphin gull is listed by the IUCN as being of "Least Concern". This is because it has a very wide range, has a stable population and an estimated total population of 10,000 to 28,000 individuals. [1]
Seabirds are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous period, and modern seabird families emerged in the Paleogene.
Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and distantly related to auks, and even more distantly 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, which is cognate with German Möwe, Danish måge, Swedish mås, Dutch meeuw, Norwegian måke/måse, and French mouette, and can still be found in certain regional dialects.
The skuas are a group of predatory seabirds with seven species forming the genus Stercorarius, the only genus in the family Stercorariidae. The three smaller skuas, the Arctic skua, the long-tailed skua, and the pomarine skua, are called jaegers in North American English.
The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the diving petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes, which also includes the albatrosses and the storm petrels.
The spotted shag or pārekareka is a species of cormorant endemic to New Zealand. Though originally classified as Phalacrocorax punctatus, it is sufficiently different in appearance from typical members of that genus that for a time it was placed in a separate genus, Stictocarbo, along with a similar species, the Pitt shag. Subsequent genetic studies show that the spotted shag's lineage is nested within the typical shags.
The red-billed gull, also known as tarāpunga and once also known as the mackerel gull, is a native 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 macaroni penguin is a species of penguin found from the Subantarctic to the Antarctic Peninsula. One of six species of crested penguin, it is very closely related to the royal penguin, and some authorities consider the two to be a single species. It bears a distinctive yellow crest that resembles macaroni, from which its name is derived. Its face and upperparts are black and sharply delineated from the white underparts. Adults weigh on average 5.5 kg (12 lb) and are 70 cm (28 in) in length. The male and female are similar in appearance; the male is slightly larger and stronger with a relatively larger bill. Like all penguins, it is flightless, with a streamlined body and wings stiffened and flattened into flippers for a marine lifestyle.
The Magellanic penguin is a South American penguin, breeding in coastal Patagonia, including Argentina, Chile, and the Falkland Islands, with some migrating to Brazil and Uruguay, where they are occasionally seen as far north as Espirito Santo. Vagrants have been found in El Salvador, the Avian Island in Antarctica, Australia, and New Zealand. It is the most numerous of the Spheniscus banded penguins. Its nearest relatives are the African penguin, the Humboldt penguin, and the Galápagos penguins. The Magellanic penguin was named after Portuguese explorer Ferdinand Magellan, who spotted the birds in 1520. The species is listed as being of Least Concern by the IUCN.
The great frigatebird is a large seabird in the frigatebird family. There are major nesting populations in the tropical Pacific Ocean, such as Hawaii and the Galápagos Islands; in the Indian Ocean, colonies can be found in the Seychelles and Mauritius, and there is a tiny population in the South Atlantic, mostly on and around St. Helena and Boatswain Bird Island.
The Chilean skua, also called the cinnamon skua, is a large predatory seabird, which breeds in Argentina and Chile, but ranges as far north as Brazil and Peru when not breeding. A relatively distinctive skua, it has a dark cap that contrasts with its cinnamon throat and lower face. Hybrids with the Falkland skua are known from southern Argentina.
The striated caracara or Forster's caracara is a Near Threatened bird of prey of the family Falconidae, the falcons and caracaras. It is found in Argentina, Chile, and the Falkland Islands. In the Falklands it is known as the Johnny rook, probably named after the Johnny penguin.
The Antarctic tern is a seabird in the family Laridae. It ranges throughout the southern oceans and is found on small islands around Antarctica as well as on the shores of the mainland. Its diet consists primarily of small fish and crustaceans. It is very similar in appearance to the closely related Arctic tern, but it is stockier, and it is in its breeding plumage in the southern summer, when the Arctic tern has shed old feathers to get its non-breeding plumage. The Antarctic tern does not migrate like the Arctic tern does, but it can still be found on a very large range. This tern species is actually more closely related to the South American tern.
The grey gull, also known as garuma gull is a medium-sized gull native to South America. Unusual among gulls, it breeds inland in the extremely dry Atacama Desert in northern Chile, although it is present as a non-breeding bird along much of the Pacific coast of South America.
Belcher's gull, also known as the band-tailed gull, is a bird in the family Laridae found along the Pacific coast of South America. It formerly included the very similar Olrog's gull as a subspecies, but that bird occurs on the Atlantic coast of South America and is now accepted as Larus atlanticus. Belcher's gull is a medium-sized gull with a blackish mantle, white head and underparts, a black band on the otherwise white tail, and a yellow bill with a red and black tip. Non-breeding adults have a brownish-black head and a white eye-ring. The name of this bird commemorates the British explorer Sir Edward Belcher who performed survey work on the Pacific coast of South America.
The imperial shag or imperial cormorant is a black and white cormorant native to southern South America, primarily in rocky coastal regions, but locally also at large inland lakes. Some taxonomic authorities, including the International Ornithologists' Union, place it in the genus Leucocarbo, others in the genus Phalacrocorax. It is also known as the blue-eyed shag, blue-eyed cormorant and by many other names, and is one of a larger group of cormorants called blue-eyed shags. The taxonomy is very complex, and several former subspecies are often considered separate species.
The blackish cinclodes is a Near Threatened passerine bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina, Chile, and on the Falkland Islands, where it is known as the tussac-bird or tussock-bird.
A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony. Colonial nesting birds include seabirds such as auks and albatrosses; wetland species such as herons; and a few passerines such as weaverbirds, certain blackbirds, and some swallows. A group of birds congregating for rest is called a communal roost. Evidence of colonial nesting has been found in non-neornithine birds (Enantiornithes), in sediments from the Late Cretaceous (Maastrichtian) of Romania.
The red-legged cormorant, also known as the red-legged shag, red-footed cormorant, red-footed shag, Gaimard's cormorant and grey cormorant, is a species of cormorant resident to the coastline of South America. It is the only member of the genus Poikilocarbo. It is non-colonial unlike most seabirds. The red-legged cormorant has not been observed wing-spreading, which is unusual among cormorant species.
The term seabird is used for many families of birds in several orders that spend the majority of their lives at sea. Seabirds make up some, if not all, of the families in the following orders: Procellariiformes, Sphenisciformes, Pelecaniformes, and Charadriiformes. Many seabirds remain at sea for several consecutive years at a time, without ever seeing land. Breeding is the central purpose for seabirds to visit land. The breeding period is usually extremely protracted in many seabirds and may last over a year in some of the larger albatrosses; this is in stark contrast with passerine birds. Seabirds nest in single or mixed-species colonies of varying densities, mainly on offshore islands devoid of terrestrial predators. However, seabirds exhibit many unusual breeding behaviors during all stages of the reproductive cycle that are not extensively reported outside of the primary scientific literature.
The Antarctic shag, sometimes referred to as the imperial cormorant, king cormorant, imperial shag, blue-eyed shag or Antarctic cormorant, is the only species of the cormorant family found in the Antarctic. It is sometimes considered conspecific with the Imperial shag.