Cormorant
Phalacrocoracidae is a family of approximately 42 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the International Ornithologists' Union (IOU) adopted a consensus taxonomy of seven genera.
The great cormorant (Phalacrocorax carbo) and the common shag (Gulosus aristotelis) are the only two species of the family commonly encountered in Britain and Ireland and "cormorant" and "shag" appellations have been later assigned to different species in the family somewhat haphazardly.
Cormorants and shags are medium-to-large birds, with body weight in the range of 0.35–5 kilograms (0.77–11.02 lb) and wing span of 60–100 centimetres (24–39 in). The majority of species have dark feathers. The bill is long, thin and hooked. Their feet have webbing between all four toes. All species are fish-eaters, catching the prey by diving from the surface. They are excellent divers, and under water they propel themselves with their feet with help from their wings; some cormorant species have been found to dive as deep as 45 metres (150 ft). They have relatively short wings due to their need for economical movement underwater, and consequently have among the highest flight costs of any flying bird.
Cormorants nest in colonies around the shore, on trees, islets or cliffs. They are coastal rather than oceanic birds, and some have colonised inland waters. The original ancestor of cormorants seems to have been a fresh-water bird.[citation needed] They range around the world, except for the central Pacific islands.
Cormorant" is a contraction probably derived from Latin corvus marinus, "sea raven". Cormoran is the Cornish name of the sea giant in the tale of Jack the Giant Killer. Indeed, "sea raven" or analogous terms were the usual terms for cormorants in Germanic languages until after the Middle Ages. The French explorer André Thévet commented in 1558: "the beak [is] similar to that of a cormorant or other corvid", which demonstrates that the erroneous belief that the birds were related to ravens lasted at least to the 16th century.
No consistent distinction exists between cormorants and shags. The names "cormorant" and "shag" were originally the common names of the two species of the family found in Great Britain – Phalacrocorax carbo (now referred to by ornithologists as the great cormorant) and Gulosus aristotelis (the European shag). "Shag" refers to the bird's crest, which the British forms of the great cormorant lack. As other species were encountered by English-speaking sailors and explorers elsewhere in the world, some were called cormorants and some shags, sometimes depending on whether they had crests or not. Sometimes the same species is called a cormorant in one part of the world and a shag in another; for example, all species in the family which occur in New Zealand are known locally as shags, including four non-endemic species known as cormorant elsewhere in their range.[citation needed] Van Tets (1976) proposed to divide the family into two genera and attach the name "cormorant" to one and "shag" to the other,but this nomenclature has not been widely adopted.
Cormorants and shags are medium-to-large seabirds. They range in size from the pygmy cormorant (Microcarbo pygmaeus), at as little as 45 cm (18 in) and 340 g (12 oz), to the flightless cormorant (Nannopterum harrisi), at a maximum size 100 cm (39 in) and 5 kg (11 lb). The recently extinct spectacled cormorant (Urile perspicillatus) was rather larger, at an average size of 6.3 kg (14 lb). The majority, including nearly all Northern Hemisphere species, have mainly dark plumage, but some Southern Hemisphere species are black and white, and a few (e.g. the spotted shag of New Zealand) are quite colourful. Many species have areas of coloured skin on the face (the lores and the gular skin) which can be bright blue, orange, red or yellow, typically becoming more brightly coloured in the breeding season. The bill is long, thin, and sharply hooked. Their feet have webbing between all four toes, as in their relatives.
Habitat varies from species to species: some are restricted to seacoasts, while others occur in both coastal and inland waters to varying degrees. They range around the world, except for the central Pacific islands.
All cormorants and shags are fish-eaters, dining on small eels, fish, and even water snakes. They dive from the surface, though many species make a characteristic half-jump as they dive, presumably to give themselves a more streamlined entry into the water. Under water they propel themselves with their feet, though some also propel themselves with their wings (see the picture, commentary, and existing reference video). Imperial shags fitted with miniaturized video recorders have been filmed diving to depths of as much as 80 metres (260 ft) to forage on the sea floor.
After fishing, cormorants go ashore, and are frequently seen holding their wings out in the sun. All cormorants have preen gland secretions that are used ostensibly to keep the feathers waterproof. Some sources state that cormorants have waterproof feathers while others say that they have water-permeable feathers.[10][11] Still others suggest that the outer plumage absorbs water but does not permit it to penetrate the layer of air next to the skin. The wing drying action is seen even in the flightless cormorant but not in the Antarctic shags or red-legged cormorants. Alternate functions suggested for the spread-wing posture include that it aids thermoregulation[14] or digestion, balances the bird, or indicates presence of fish. A detailed study of the great cormorant concluded there is little doubt that is serves to dry the plumage.
Cormorants are colonial nesters, using trees, rocky islets, or cliffs. The eggs are a chalky-blue colour. There is usually one brood a year. Parents regurgitate food to feed their young.
Cormorant culling the intentional killing of cormorants by humans for the purposes of wildlife management. It has been practiced for centuries, with supporters of culling generally arising from the angling community. Culling techniques may involve the killing of birds, the destruction of eggs, or both. Historically, culls have occurred to protect the interests of recreational and commercial fishermen who perceive the animals to be competing with them for their intended catch or for the prey of their intended catch. Since the 1960s, the growing aquaculture industry has undertaken cormorant culls to protect its farmed fish and crustacean stocks. Opponents of cormorant culling include conservation groups such as the National Audubon Society, Cormorant Defenders International and Sea Shepherd.
Humans have used cormorants' fishing skills in various places in the world. Archaeological evidence suggests that cormorant fishing was practised in Ancient Egypt, Peru, Korea and India, but the strongest tradition has remained in China and Japan, where it reached commercial-scale level in some areas.[37] In Japan, cormorant fishing is called ukai (鵜飼) and is performed by a fisherman known as an usho.[38] Traditional forms of ukai can be seen on the Nagara River in the city of Gifu, Gifu Prefecture, where cormorant fishing has continued uninterrupted for 1300 years, or in the city of Inuyama, Aichi. In Guilin, Guangxi, cormorants are famous for fishing on the shallow Li River. In Gifu, the Japanese cormorant (P. capillatus) is used; Chinese fishermen often employ great cormorants (P. carbo).[39] In Europe, a similar practice was also used on Doiran Lake in the region of Macedonia. James VI and I appointed a keeper of cormorants, John Wood, and built ponds at Westminster to train the birds to fish.
In a common technique, a snare is tied near the base of the bird's throat, which allows the bird only to swallow small fish. When the bird captures and tries to swallow a large fish, the fish is caught in the bird's throat. When the bird returns to the fisherman's raft, the fisherman helps the bird to remove the fish from its throat. The method is not as common today, since more efficient methods of catching fish have been developed, but is still practised as a cultural tradition.
In Japan, environmental changes threaten traditional ukai because of reduced numbers of the ayu river fish that cormorants are used to catch.
Cormorants feature in heraldry and medieval ornamentation, usually in their "wing-drying" pose, which was seen as representing the Christian cross, and symbolizing nobility and sacrifice. For John Milton in Paradise Lost, the cormorant symbolizes greed: perched atop the Tree of Life, Satan took the form of a cormorant as he spied on Adam and Eve during his first intrusion into Eden.[42]
In some Scandinavian areas, they are considered good omen; in particular, in Norwegian tradition spirits of those lost at sea come to visit their loved ones disguised as cormorants. For example, the Norwegian municipalities of Røst, Loppa and Skjervøy have cormorants in their coat of arms. The symbolic liver bird of Liverpool is commonly thought to be a cross between an eagle and a cormorant.
In Homer's epic poem The Odyssey, Odysseus (Ulysses) is saved by a compassionate sea nymph who takes the form of a cormorant.
In 1853, a woman wearing a dress made of cormorant feathers was found on San Nicolas Island, off the southern coast of California. She had sewn the feather dress together using whale sinews. She is known as the Lone Woman of San Nicolas and was later baptised "Juana Maria" (her original name is lost). The woman had lived alone on the island for 18 years before being rescued. When removed from San Nicolas, she brought with her a green cormorant dress she made; this dress is reported to have been removed to the Vatican.[citation needed] Her story, which includes the feather dress, was fictionalized in the children's novel Island of the Blue Dolphins.
In 1853, a woman wearing a dress made of cormorant feathers was found on San Nicolas Island, off the southern coast of California. She had sewn the feather dress together using whale sinews. She is known as the Lone Woman of San Nicolas and was later baptised "Juana Maria" (her original name is lost). The woman had lived alone on the island for 18 years before being rescued. When removed from San Nicolas, she brought with her a green cormorant dress she made; this dress is reported to have been removed to the Vatican.[citation needed] Her story, which includes the feather dress, was fictionalized in the children's novel Island of the Blue Dolphins.
The bird has inspired numerous writers, including Amy Clampitt, who wrote a poem called "The Cormorant in its Element". The species she described may have been the pelagic cormorant, which is the only species in the temperate U.S. with the "slim head ... vermilion-strapped" and "big black feet" that she mentions.[citation needed]
A cormorant representing Blanche Ingram appears in the first of the fictional paintings by Jane in Charlotte Brontë's novel Jane Eyre:
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