The brown pelican ( Pelecanus occidentalis ) is a North American bird of the Pelikan family, Pelecanidae. It is one of three pelican species found in America and one of only two that feeds by diving in water. It is found on the Atlantic Coast from Nova Scotia to the mouth of the Amazon River, and along the Pacific Coast from British Columbia to northern Chile, including the Galapagos Islands. The subspecies that nominate in their breeding coat have a white head with a yellowish wash on the crown. Neck and neck are dark maroon. The upper side of the neck has a white line along the base of the sugar bag, and the lower front neck has a pale yellowish spots. Men and women are similar, but women are slightly smaller. Unmarried adults have white heads and necks. The pink skin around the eyes becomes dull and gray in non-married seasons. It has no red color, and the pockets are very reddish yellow and the legs are gray-gray.
Pelican chocolate mainly eats fish, but occasionally eat amphibians, crustaceans, and eggs and birds. It nests in colonies in remote areas, often on islands, vegetated soils among sand dunes, shrubs and trees, and mangroves. Females lay two or three ovals, whitish white eggs. Incubation takes 28 to 30 days with the task of sharing the gender. The newly hatched pink chickens turn gray or black within 4 to 14 days. Approximately 63 days are required for chicks to mature. Six to nine weeks after hatching, teens leave the nest, and gather in small groups known as pods.
The chocolate pelican is a national bird of Saint Martin, Barbados, Saint Kitts and Nevis, as well as the Turks and Caicos Islands, and the official bird of the state of Louisiana. It has been rated as the least-visited species by the International Union for Nature Conservation. It was registered under the Endangered Species Act of the United States from 1970 to 2009, as pesticides such as dieldrin and DDT threaten its future in the Southeastern United States and California. In 1972, the use of DDT was banned in Florida, followed by other parts of the United States. Since then, the brown pelicans population has increased. In 1903, Theodore Roosevelt set aside the first National Wildlife Refuge, Pelikan Island in Florida, to protect the species from hunters.
Video Brown pelican
Taxonomy
The brown pelican was described by the Swedish zoologist Carl Linnaeus in 1266 edition of 12th edition of Systema Naturae, where it was named binomial Pelecanus occidentalis. This belongs to the New Clade world of the genus Pelecanus .
Five subspecies of brown pelican are recognized:
- P. o.Ã, californicus Ã, (Ridgway, 1884) - This subspecies breed on the Pacific coast of California and Baja California, and south to Jalisco. Its non-breeding range extends north along the Pacific coast to British Columbia, and south to Guatemala. It is rarely found in El Salvador.
- P. o. carolinensis Ã, (Gmelin, 1789) - This subspecies breed in the eastern United States of southern Maryland along the Atlantic, Gulf and Caribbean coasts and south to Honduras and its Pacific coast, Kosta Rika, and Panama. Its non-breeding range is from southern New York to Venezuela.
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o.a, occidentalis Ã, (Linnaeus, 1766) - This subspecies breed in the Great and Small Antilles, the Bahamas, and along the Caribbean coast at West Indies, Colombia and Venezuela, to Trinidad and Tobago.
- P. o.Ã, murphyi Ã, (Wetmore, 1945) - This species is found from western Colombia to Ecuador, and is a non-breeding visitor to northern Peru.
- P. o.Ã, urinator Ã, (Wetmore, 1945) - This subspecies is found in the Galapagos Islands.
The brown pelican is part of the clade that includes Peruvian pelicans ( P. sero ) and the white American pelican ( P. Erythrorhynchos ). Pericopian pelicans were previously treated as subspecies of brown pelicans, but are now regarded as separate species based on their much larger size (about twice the weight of brown pelican), differences in color and feathers, and lack of hybridisation between forms despite much overlap. In contrast, hybridization between brown and white pelicans is possible.
In 1931, James L. Peters separated the white American pelican and brown pelicans (including Peruvian pelicans) into monospecific subgenera. This separation was also supported by Jean Dorst and Raoul J. Mougin in 1979. The pelican spot-billed and pink pelican supported were considered species of brothers by Andrew Elliott in 1992 and Joseph B. Nelson in 2005, and the distinction between brown pelicans and Peru found the most in families pelicans. In 1993, Paul Johnsgard hypothesized that pelicans belonged to the ancestors of South Asia or Africa, and spread through northern Asia and Australia before finally coming to North America. This hypothesis would imply that, unless the American brown and white pelican pelicans are produced from several North American invasions, they would become taxa. However, trees derived from genetic data do not agree. In 1990, Charles Sibley and John E. Ahlquist's Unweighted Pair Group Method with Arithmetic Mean trees (UPGMA) based on DNA-DNA hybridization data found that white American pelicans, pink pelicans, large white pelican, and Australian pelicans. are brothers species, and brown pelicans are the most distinct of all.
Maps Brown pelican
Description
Pelican chocolate is the smallest of the eight species of pelicans, but is often one of the larger sea birds within their reach. It measures 1 to 1.52 m (3 ft 3 in to 5 ft 0 in) in length and has a wingspan of 2.03 to 2.28 m (6 ft. 8 in. To 7 ft. 6 in). The adult weights can range from 2 to 5 kg (4.4 to 11.0 pounds), about half the weight of other pelicans found in America, the Peruvian white pelicans and the Americans. The average weight in Florida of 47 women was 3.17 kg (7.0 pounds), while 56 men were 3.7 kg (8.2 lb). Like all pelicans, it has a very long bill, measuring 280 to 348 mm (11.0 to 13.7 inches) in length.
The subspecies that nominate in their breeding coat have a white head with a yellowish wash on the crown. Neck and neck are dark maroon. The upper side of the neck has a white line along the base of the sugar bag, and the bottom of the foreneck has a pale yellowish spots. The hairs in the middle of the nape are elongated, forming short and deep chestnut feathers. It has a silver gray mantle, Ã, scapulars , and a wing top cover (feather on the upper side of the wing), with a brownish tone. The lower cover has a dark base, which provides the leading edge of the wing with a successive appearance. The uppertail cover (feather above the tail) is silvery white in the middle, forming pale lines. Median (between larger and smaller cover), primary (connected to the distal forelimb), secondary (connected to the ulna), and larger cover (the largest outer feather, the topwing rows) are blackish, with the introduction the white and secondary shafts have a variable silver-gray periphery. The tertials (bristles that arise in the brachial region) are silver gray with a brownish tinge. The lower part has a grayish-brown color with a white axle to the outer primary feathers. Axilla and dark secret plumage, with a large, silver center area of ​​gray. The tail is dark gray with a variable silver cast. The lower mandibular is blackish, with a crisp greenish cassock on the bottom to drain the water while removing the prey. His breasts and stomach are dark, and his legs and feet are black. It has a grayish white bill colored with chocolate and mixes with pale carmine spots. The peak is short and pale reddish brown. The back, buttocks and tail are striped in gray and dark brown, sometimes with rusty hue. Men and women are similar, but women are slightly smaller. It's soaring because of the internal air sacks under the skin and the bones. It is graceful in the air because it is awkward on land.
Non-cultured adults have white heads and necks, and pre-breeding adults have creamy yellow heads. The pink skin around the eyes becomes dull and gray in the non-breeding season. It has no red hue, and the pockets are very yellow and brown and gray in gray. It has a pale blue to yellowish white color that becomes brown during the mating season. During courtship, the bill becomes pink pale orange, redder at the end, and the bag is blackish. Later in the breeding season, the bill became gray ash pale in most of the mandible's upper and lower third jaws.
Teenagers are the same, but overall the chocolate is grayish and has a pale lower part. The head, neck, and thighs are blackish brown, and the stomach is dull white. Males are similar to full adult females, although the male head feathers are a bit stiff. Tail and fly feathers are more brown than adults. It has a short, brown top cover that is often darker on a larger cover, and a gray-brownish gray bottom cover with a white ribbon in the center. The irides are dark brown and bluish facial skin. It has a yellow gray orange horn bill near the end, with dark gray to a pink gray bag. It acquires adult fur in over 3 years, when the hair on the neck becomes pale, the top becomes striped, the wing top cover and the larger median becomes the grayer, and the stomach gets dark spots.
Pelican chocolate is easily distinguished from American white pelicans with white fur, smaller size, and diving habits for fish from the air, as opposed to cooperative fishing from the surface. This and Peruvian pelicans are the only true marine pelicans species.
Pelican chocolate produces a variety of harsh, grunting noises, such as low-pitched hrrraa-hrra, during displays. Adults also rarely sound low, while young people often scream.
Distribution and habitat
Pelican chocolate lives in the Atlantic, Gulf, and Pacific Coast of America. On the Atlantic Coast, found from Nova Scotia to the mouth of the Amazon River. Along the Pacific Coast, it is found from British Columbia to south-central Chile, including the Galapagos Islands. After nesting, North American birds move in a herd further north along the coast, returning to warm waters for the winter. In the non-breeding season, it is found as far north as Canada. It is a rare and irregular visitor in southern Piura in Peru, where it is generally replaced by Peruvian pelicans, and can occur as a southern non-breeding visitor at least to Ica during El NiÃÆ' Â ± o years. A small number of brown pelicans have been recorded from Arica in northern Chile. This is quite common along the coast of California, South Carolina, North Carolina, Georgia, West Indies, and many Caribbean islands as far south as Guyana. Along the Gulf Coast, he inhabited Alabama, Texas, Florida, Mississippi, Louisiana, and Mexico.
Pelican chocolate is a strict marine species, mainly inhabiting subtidal sea, warm estuary, and pelagic sea waters. It is also found in mangrove swamps, and prefers the shallow waters, especially near the salt bay and the coast. It avoids open sea, rarely reaches more than 20 miles from shore. Some immature birds may get lost to the inland freshwater lake. The range can also overlap with Peruvian pelicans in some areas along the Pacific coast of South America. It perched on rocks, water, rocky cliffs, docks, docks, sand beaches, and mud plains.
Migration
Most brown pelican populations are nonmigratory and spread (species that move from their birthplace to breeding sites, or breeding places to other breeding sites), although some migrations are observed, especially in the northern regions of their reach, but these movements are often uncertain , depending on local conditions. To the south, they are bums (found out of the usual range) in Tierra del Fuego. They have been recorded off the east coast of Brazil, in Alagoas. Rare ground bum, commonly caused by hurricanes or El Nià ± a phenomena, has been reported from the Colombian Andes. They were first recorded in July 2009 in the Interandean Valley where they stayed for at least 161 days. There are four notes deep in the AmazÃÆ'Â'nia Legal hinterland along the Amazon River and its tributaries.
Behavior
Chocolate pelican is a very friendly bird; he lives in the group of both sexes throughout the year. In the flight level, the chocolate brows flew in groups, with their heads held on their shoulders and their bills rested on their folded neck. They may fly in formation V, but usually in regular lines or single files, often low on the surface of the water. To remove water from the nasal passages, they have a narrower internal area of ​​the nostrils.
Feeding
Pelican chocolate is a fish, especially eating fish. Menhaden may reach 90% of its diet, and anchovy supply is essential for the successful nesting of brown pelicans. Other fish that are preyed with some regularity include pigfish, pinfish, herring, sheepshead, silversides, mullet, sardines, and mini fish. Non-fish species include crustaceans, especially shrimp, and occasionally eat amphibians and eggs and birds' nests (herons, common murders and species themselves).
When the brown pelicans fly with a maximum height of 18 to 21 m (60 to 70 feet) above the ocean, it can see the flow of fish while flying. When looking for food, he dives first like a kingfisher bird, often drowning completely beneath the temporary surface as he catches the prey. After surfacing, he spilled water from his throat bag before swallowing his catch. Only Peruvian pelicans share this active feeding style (though the species never dive from very high altitudes), while other pelicans look for more inactive foods by scooping up the shrunken fish while swimming on the water. This is an occasional target of kleptoparasitism by other fish-eating birds such as seagulls, skuas, and sea eagles. They are able to drink salt water because of the high capacity of their salt glands to secrete salt.
Breeding
The brown pelican is a monogamous rancher in the breeding season, but not in pairs for life. Peak season nest during March and April. Men choose nesting places and perform head movement to attract women. On the proposed nest site, the main courtship is displayed as the head swaying, bending, spinning, and erect (standing on its feet without any support) done by both sexes. They may also be accompanied by a low call raaa .
Once a pair forms a bond, clear communication between them is minimal. It is a colonial species, with several colonies retained over the years. Perhaps because of disruption, lice, or changes in food supply, the colony often shifts. These nests are in remote areas, often on islands, where vegetation is between dunes, shrubs and trees, and in the mangrove forests, though sometimes on cliffs, and less frequently in bushes or small trees. The nesting area is favored, as each region may be at a distance of only 1 m (3.3 m) from each other. They are usually built by women from reeds, leaves, gravel, and sticks, and consist of traces of hairy protected with 10 to 25 cm (3.9-9.8 inches) of soil and debris. They are usually found 0.9 to 3 m (3 to 10 feet) above the ground. Renesting can occur if the eggs disappear from the nest early in the breeding season.
There are usually two to three, or sometimes even four, oval eggs in a clutch, and only one parent is raised per year. Calcareous white eggs, and can measure about 76 mm (3.0 inches) and 51 mm (2.0 inches) wide. Incubation takes 28 to 30 days with both sexes sharing tasks, keeping the eggs warm by holding them above or under their webbed feet. It takes 28 to 30 days for the eggs to hatch, and about 63 days to mature. After that, teenagers leave the nest and collect it into small groups known as pods. The newly hatched chicks are pink and weigh about 60 g (0.13 pounds). Within 4 to 14 days, they turn gray or black. After that, they develop a white coat, black or grayish. The success of fledging may be as high as 100% for first hatching girls, 60% for second chick, and only 6% for third chick.
Parents spew food that has been ingested to young children until they reach their fledging stage. After about 35 days, young business out of the nest by foot. Young start flying about 71 to 88 days after hatching. Adults stay with them for some time afterwards and keep feeding them. In the 8 to 10 months period during which they are treated, stinging pelicans are fed by digested foods, partially digested about 70 kg (150 pounds) of fish. The young reach sexual maturity (and full adult hair) anywhere from three to five years. The brown pelikan has been recorded to have lived for over 31 years in captivity.
Predators and parasites
Predations sometimes in colonies, and egg and youth predators (usually small nests threatened but also sometimes to seed size depending on the size of the predator) may include gulls, raptors (especially bald eagles), crocodiles, vultures, ravens, and corvids. Predation is likely to decrease if the colony is on an island. Predation in adult brown pelicans is rarely reported, but cases where they have fallen prey to bald eagles have been reported. Also, South American sea lions and unknown large sharks have been observed to prey on mature brown pelicans by catching them from below while birds sit in the ocean waters. Invasive red invasive fire ants are known to precede the hatchling. Like all pelicans, brown pelicans are very sensitive to human interference (including tourists or fishermen) in their nests, and may even leave their nests. Due to its size, non-nesting adults are rarely visited. The chocolate pelicans have some parasitic worms like Petagiger , Echinochasmus , Phagicola longus , Mesostephanus appendiculatoides , Contracaecum multipapillatum , and Contracaecum bioccai , from its black prey food, white mullet, and other fish species.
Relationships with humans
Pelican chocolate is now a densely populated coastal area and tolerated to varying degrees by fishermen and sailors. At the beginning of the 20th century, hunting was the leading cause of his death, and people still hunt adults for their feathers and collect eggs on the Caribbean coast, in Latin America, and sometimes in the United States, even though protected under the Migration Act. Invite the Bird Treaty of 1918.
Cultural depictions
Pelican chocolate is a national bird of Saint Martin, Barbados, Saint Kitts and Nevis, and the Turks and Caicos Islands. In 1902, it became part of Louisiana's official seal and, in 1912, a pelicans and his son became part of Flag of Louisiana as well. One of the nicknames of the state of Louisiana is "The Pelican State", and the chocolate pelicans are the official birds of the state of Louisiana. This is one of the mascots of Tulane University, which is in its seal, and also in the symbol of the University of the West Indies. The National Basketball Association (NBA) in New Orleans Pelicans is named in honor of the brown pelicans.
In the 1993 film The Pelican Brief, based on a novel of the same name by John Grisham, a legal speculation speculates that the murder of two justices is motivated by the desire to drill for oil on the Louisiana Swamp Land which is a threatened brown pelican habitat extinct. That same year, Jurassic Park shows a bunch of Brown pelikan at the end of the movie. In 1998, American conductor David Woodard requested for a California chocolate pelican at the seaward boundary of the coastal embankment where the animal fell. In the Disney/Pixar 2003 film Finding Nemo, the chocolate pelicans (voiced by Geoffrey Rush in Australian accents) is illustrated as a virtuous friendly speaking character named Nigel.
Status and preservation
Since 1988, brown pelicans have been rated as the least aware of the IUCN Red List of Endangered species based on their large ranks - more than 20,000 km 2 (7700Ã, mi 2 ) - and an increasing population trend. Population size is also well beyond the threshold for vulnerable species. The nominated race population is estimated to be at least 290,000 in the West Indies, and 650,000 globally. In 1903, Theodore Roosevelt set aside the Pelican Island, now known as Pelican Island Wildlife Refugee, to protect only brown pelicans from hunters.
Beginning in the 1940s with the discovery and use of extensive pesticides such as DDT, the brown pelican population drastically decreased due to lack of successful breeding. By the 1960s, it had virtually disappeared along the Gulf Coast and, in southern California, it had experienced almost total reproductive failure, due to the use of DDT in the United States. The chocolate pelicans were listed under the US Endangered Species Act from 1970 to 2009. A research group from Tampa University, led by Ralph Schreiber, conducted a study at Tampa Bay, and found that DDT caused the pelican egg shell to become too thin. support embryo to maturity. In 1972, the United States Environmental Protection Agency (USEPA) banned the use of DDT in the United States and restricted the use of other pesticides. There has been a decrease in the level of chemical contaminants in pelican brown eggs ever since, and the corresponding increase in nesting success. He went extinct in 1963 in Louisiana. Between 1968 and 1980, the reintroduction program of the Louisiana Department of Fisheries and Maritime reshaped brown pelicans, and the number of populations in California and Texas was restored due to better reproduction and natural recolonisation of species. In 1985, the population in the eastern United States, including Florida, Georgia, South Carolina, Alabama, and north along the Atlantic Coast, has recovered and the species was removed from the Endangered Species List. Its population has grown by about 68% per decade over a 40-year period in North America, and this trend seems to continue. It is still listed as endangered in the Pacific Coast region from its reach and in the southern and central United States. Although the US Gulf Coast population in Louisiana and Texas is still listed as endangered, they have recently estimated about 12,000 breeding pairs.
Note
References
External links
- "Brown Pelican" media. Bird Bird Collection .
- Photo Gallery of Brown Pelican at VIREO (Drexel University)
- Field Guide Page on Flickr
- Interactive range map Pelecanus occidentalis on the IUCN Red List map
Source of the article : Wikipedia
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