American white pelican | |
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Flying in Dallas, USA | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Pelecanidae |
Genus: | Pelecanus |
Species: | P. erythrorhynchos |
Binomial name | |
Pelecanus erythrorhynchos Gmelin, 1789 | |
Breeding Migration Year-round Nonbreeding | |
Synonyms | |
Pelecanus erythrorhynchus( lapsus ) |
The American white pelican (Pelecanus erythrorhynchos) is a large aquatic soaring bird from the order Pelecaniformes. It breeds in interior North America, moving south and to the coasts, as far as Costa Rica, in winter. [3]
The American white pelican was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae . He placed it with the other pelicans in the genus Pelecanus and coined the binomial name Pelecanus erythrorhynchos. [4] Gmelin based his description on the "rough-billed pelican" that had been described in 1785 by the English ornithologist John Latham. Latham had access to three specimens that had been brought to London from New York and the Hudson Bay area of North America. [5] [6] The scientific name means "red-billed pelican", from the Latin term for a pelican, Pelecanus, and erythrorhynchos, derived from the Ancient Greek words erythros (ἐρυθρός, "red") + rhynchos (ῥύγχος, "bill"). [7] The species is monotypic: no subspecies are recognised. [8]
The American white pelican rivals the trumpeter swan, with a similar overall length, as one of the longest birds native to North America. Both very large and plump, it has an overall length of about 50–70 in (130–180 cm), courtesy of the huge beak which measures 11.3–15.2 in (290–390 mm) in males and 10.3–14.2 in (260–360 mm) in females. It has a wingspan of about 95–120 in (240–300 cm). [9] The species also has the second-largest average wingspan of any North American bird, after the California condor. This large wingspan allows the bird to easily use soaring flight for migration. Body weight can range between 7.7 and 30 lb (3.5 and 13.6 kg), although typically these birds average between 11 and 20 lb (5.0 and 9.1 kg). [10] One mean body mass of 15.4 lb (7.0 kg) was reported. [10] Another study found mean weights to be somewhat lower than expected, with eleven males averaging 13.97 lb (6.34 kg) and six females averaging 10.95 lb (4.97 kg). [11] Among standard measurements, the wing chord measures 20–26.7 in (51–68 cm) and the tarsus measures 3.9–5.4 in (9.9–13.7 cm) long. [12] The plumage is almost entirely bright white, except for the black primary and secondary remiges, which are hardly visible except in flight. From early spring until after breeding has finished in mid-late summer, the breast feathers have a yellowish hue. After moulting into the eclipse plumage, the upper head often has a grey hue, as blackish feathers grow between the small wispy white crest. [3]
The bill is huge and flat on the top, with a large throat sac below, and, in the breeding season, is vivid orange in color as is the bare skin around the eye and the feet. Iris coloration depends upon age and season, ranging from bright white to hazel to blue-gray. [13] In the breeding season, both sexes grow a laterally flattened keratinous "horn" on the upper bill, located about one-third the bill's length behind the tip. This is the only one of the eight species of pelican to have a bill "horn". The horn is shed after the birds have mated and laid their eggs. Outside the breeding season, the bare parts become duller in color, with the naked facial skin yellow and the bill, pouch, and feet a dull pink-orange. [3]
Apart from the difference in size, males and females look exactly alike. Immature birds have light grey plumage with darker brownish nape and remiges. Their bare parts are dull grey. Chicks are naked at first, then grow white down feathers all over, before moulting to the immature plumage. [3]
American white pelicans nest in colonies of several hundred pairs on islands in remote brackish and freshwater lakes of inland North America. The most northerly nesting colony can be found on islands in the rapids of the Slave River between Fort Fitzgerald, Alberta, and Fort Smith, Northwest Territories. Several groups have been visiting the bird sanctuary at Useless Bay in the state of Washington since 2015. About 10–20% of the population uses Gunnison Island in the Great Basin's Great Salt Lake as a nesting ground. The southernmost colonies are in southeastern Ontario and western Nevada. [14] [15]
They winter on the Pacific and Gulf of Mexico coasts from central California and Florida south to Costa Rica, and along the Mississippi River at least as far north as St. Paul, Minnesota. In winter quarters, they are rarely found on the open seashore, preferring estuaries, bays, and lakes. They cross deserts and mountains but avoid the open ocean on migration. [3] But stray birds, often blown off course by hurricanes, have been seen in the Caribbean. In Colombian territory, it was recorded first on February 22, 1997, on the San Andrés Island, where they might have been swept by Hurricane Marco which passed nearby in November 1996. Since then, there have also been a few observations likely to pertain to this species on the Colombian mainland, e.g. at Calamar. [16]
Wild American white pelicans may live for more than 16 years. In captivity, the record lifespan stands at over 34 years. [3]
Unlike the brown pelican (P. occidentalis), the American white pelican does not dive for its food. Instead, it catches its prey while swimming. Each bird eats more than four pounds (1.8 kg) of food a day. [17] The fish taken by pelicans can range from the size of minnows to 3.5-pound pickerels. [18] Typical fish prey include Cypriniformes like common carp (Cyprinus carpio), Lahontan tui chub (Gila bicolor obesa), [19] minnows, [20] and shiners. [21] Perciformes like Sacramento perch (Archoplites interruptus) or yellow perch (Perca flavescens), [21] Salmoniformes like rainbow trout (Oncorhynchus mykiss) and salmon, [20] Siluriformes (catfish), [22] and jackfish. [23] Other animals eaten by these birds are crayfish, amphibians, and sometimes larval salamanders. [24] Birds nesting on saline lakes, where food is scarce, will travel great distances to better feeding grounds. [3]
American white pelicans like to come together in groups of a dozen or more birds to feed, as they can thus cooperate and corral fish to one another. When this is not easily possible – for example in deep water, where fish can escape by diving out of reach – they prefer to forage alone. But the birds also steal food on occasion from other birds, a practice known as kleptoparasitism. White pelicans are known to steal fish from other pelicans, gulls, and cormorants from the surface of the water and, in one case, from a great blue heron while both large birds were in flight. [3] [25]
As noted above, they are colonial breeders, with up to 10,000 pairs per site. [26] The birds arrive on the breeding grounds in March or April; nesting starts between early April and early June. During the breeding season, both males and females develop a pronounced bump on the top of their large beaks. This conspicuous growth is shed by the end of the breeding season.
The nest is a shallow depression scraped in the ground, into which some twigs, sticks, reeds, or similar debris have been gathered. After about one week of courtship and nest-building, the female lays a clutch of usually two or three eggs, sometimes just one, sometimes up to six.
Both parents incubate for about one month. The young leave the nest 3–4 weeks after hatching; at this point, usually only one young per nest has survived. They spend the following month in a creche or "pod", moulting into immature plumage and eventually learning to fly. After fledging, the parents care for their offspring some three more weeks, until the close family bond separates in late summer or early fall, and the birds gather in larger groups on rich feeding grounds in preparation for the migration to the winter quarters. They migrate south by September or October. [3]
Occasionally, these pelicans may nest in colonies on isolated islands, which is believed to significantly reduce the likelihood of mammalian predation. Red foxes and coyotes prey upon colonies that they can access, and several gulls have been known to prey on pelican eggs and nestlings (including herring, ring-billed, and California gull), as well as common ravens. Young pelicans may be hunted by great horned owls, red-tailed hawks, bald eagles, and golden eagles. The pelicans react to mammalian threats differently from avian threats. Though fairly approachable while feeding, the pelicans may temporarily abandon their nests if a human closely approaches the colony. If the threat is another bird, however, the pelicans do not abandon the nest and may fight off the interloper by jabbing at them with their considerable bills. [27] Full-grown pelicans have few predators. Only red foxes and coyotes are known to prey on nesting adults on rare occasions. [28]
This species is protected by the Migratory Bird Treaty Act of 1918. It has the California Department of Fish and Game protective status California species of special concern (CSC). On a global scale, however, the species is common enough to qualify as a Species of Least Concern according to the IUCN. [1]
Habitat loss is the largest known cause of nesting failure, with flooding and drought being recurrent problems. Human-related losses include entanglement in fishing gear, boating disturbance, and poaching as well as additional habitat degradation. [29]
There was a pronounced decline in American white pelican numbers in the mid-20th century, attributable to the excessive spraying of DDT, endrin, and other organochlorides in agriculture as well as widespread draining and pollution of wetlands. But populations have recovered well after stricter environmental protection laws came into effect, and are stable or slightly increasing today. By the 1980s, more than 100,000 adult American white pelicans were estimated to exist in the wild, with 33,000 nests altogether in the 50 colonies in Canada, and 18,500 nests in the 14–17 United States colonies. Shoreline erosion at breeding colonies remains a problem in some cases, as are the occasional mass poisonings when pesticides are used near breeding or wintering sites. [3]
The bald eagle is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle, which occupies the same niche as the bald eagle in the Palearctic. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting.
Pelicans are a genus of large water birds that make up the family Pelecanidae. They are characterized by a long beak and a large throat pouch used for catching prey and draining water from the scooped-up contents before swallowing. They have predominantly pale plumage, except for the brown and Peruvian pelicans. The bills, pouches, and bare facial skin of all pelicans become brightly coloured before the breeding season.
The great blue heron is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North and Central America, as well as far northwestern South America, the Caribbean and the Galápagos Islands. It is occasionally found in the Azores and is a rare vagrant to Europe. An all-white population found in south Florida and the Florida Keys is known as the great white heron. Debate exists about whether these white birds are a color morph of the great blue heron, a subspecies of it, or an entirely separate species.
The white-tailed eagle, sometimes known as the 'sea eagle', is a large bird of prey, widely distributed across temperate Eurasia. Like all eagles, it is a member of the family Accipitridae which also includes other diurnal raptors such as hawks, kites, and harriers. One of up to eleven members in the genus Haliaeetus, which are commonly called sea eagles, it is also referred to as the white-tailed sea-eagle. Sometimes, it is known as the ern or erne, gray sea eagle and Eurasian sea eagle.
The black-necked grebe or eared grebe is a member of the grebe family of water birds. It was described in 1831 by Christian Ludwig Brehm. Its breeding plumage features distinctive ochre-coloured feathers which extend behind its eye and over its ear coverts. The rest of the upper parts, including the head, neck, and breast, are coloured black to blackish brown. The flanks are tawny rufous to maroon-chestnut, and the abdomen is white. In its non-breeding plumage, this bird has greyish-black upper parts, including the top of the head and a vertical stripe on the back of the neck. The flanks are also greyish-black. The rest of the body is a white or whitish colour. The juvenile has more brown in its darker areas. This species is present in parts of Africa, Eurasia, and the Americas.
The brown pelican is a bird of the pelican family, Pelecanidae, one of three species found in the Americas and one of two that feed by diving into water. It is found on the Atlantic Coast from New Jersey to the mouth of the Amazon River, and along the Pacific Coast from British Columbia to Peru, including the Galapagos Islands. The nominate subspecies in its breeding plumage has a white head with a yellowish wash on the crown. The nape and neck are dark maroon–brown. The upper sides of the neck have white lines along the base of the gular pouch, and the lower fore neck has a pale yellowish patch. The male and female are similar, but the female is slightly smaller. The nonbreeding adult has a white head and neck. The pink skin around the eyes becomes dull and gray in the nonbreeding season. It lacks any red hue, and the pouch is strongly olivaceous ochre-tinged and the legs are olivaceous gray to blackish-gray.
The double-crested cormorant is a member of the cormorant family of water birds. It is found near rivers and lakes and in coastal areas and is widely distributed across North America, from the Aleutian Islands in Alaska down to Florida and Mexico. Measuring 70–90 cm (28–35 in) in length, it is entirely black except for a bare patch of orange-yellow facial skin and some extra plumage that it exhibits in the breeding season when it grows a double crest in which black feathers are mingled with white. Five subspecies are recognized. It mainly eats fish and hunts by swimming and diving. Its feathers, like all cormorants, are not waterproof, and it must dry them out after spending time in the water. Once threatened by the use of DDT, the numbers of this bird have increased markedly in recent years.
The Australian pelican is a large waterbird in the family Pelecanidae, widespread on the inland and coastal waters of Australia and New Guinea, also in Fiji, parts of Indonesia and as a vagrant in New Zealand. It is a predominantly white bird with black wings and a pink bill. It has been recorded as having the longest bill of any living bird. It mainly eats fish, but will also consume birds and scavenge for scraps if the opportunity arises.
The common tern is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migratory, wintering in coastal tropical and subtropical regions. Breeding adults have light grey upperparts, white to very light grey underparts, a black cap, orange-red legs, and a narrow pointed bill. Depending on the subspecies, the bill may be mostly red with a black tip or all black. There are several similar species, including the partly sympatric Arctic tern, which can be separated on plumage details, leg and bill colour, or vocalisations.
The common merganser or goosander (Eurasian) is a large sea duck of rivers and lakes in forested areas of Europe, Asia, and North America. The common merganser eats mainly fish. It nests in holes in trees.
The Dalmatian pelican is the largest member of the pelican family and perhaps the world's largest freshwater bird, although rivaled in weight and length by the largest swans. They are elegant soaring birds, with wingspans rivaling those of the great albatrosses, and their flocks fly in graceful synchrony. With a range spanning across much of Central Eurasia, from the eastern Mediterranean in the west to the Taiwan Strait in the east, and from the Persian Gulf in the south to Siberia in the north, it is a short-to-medium-distance migrant between breeding and overwintering areas. No subspecies are known to exist over its wide range, but based on size differences, a Pleistocene paleosubspecies, P. c. palaeocrispus, has been described from fossils recovered at Binagadi raion in Azerbaijan.
The great white pelican also known as the eastern white pelican, rosy pelican or simply white pelican is a bird in the pelican family. It breeds from southeastern Europe through Asia and Africa, in swamps and shallow lakes.
Forster's tern is a tern in the family Laridae. The genus name Sterna is derived from Old English "stearn", "tern", and forsteri commemorates the naturalist Johann Reinhold Forster.
The pink-backed pelican is a bird of the pelican family. It is a resident breeder in the swamps and shallow lakes of Africa and southern Arabia; it has also apparently been extirpated from Madagascar.
The spot-billed pelican or gray pelican is a member of the pelican family. It breeds in southern Asia from southern Iran across India east to Indonesia. It is a bird of large inland and coastal waters, especially large lakes. At a distance they are difficult to differentiate from other pelicans in the region although it is smaller but at close range the spots on the upper mandible, the lack of bright colours and the greyer plumage are distinctive. In some areas these birds nest in large colonies close to human habitations.
The reddish egret is a medium-sized heron that is a resident breeder in Central America, the Bahamas, the Caribbean, the Gulf Coast of the United States, and Mexico. The egret is known for its unusual foraging behavior compared to other herons as well as its association with mud flats, its habitat of choice.
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 yellow-billed stork is a large African stork species in the family Ciconiidae. It is widespread south of the Sahara and also occurs in Madagascar.
The Goliath heron, also known as the giant heron, is a very large wading bird of the heron family, Ardeidae. It is found in sub-Saharan Africa, with smaller, declining numbers in Southwest and South Asia.
The maguari stork is a large species of stork that inhabits seasonal wetlands over much of South America, and is very similar in appearance to the white stork; albeit slightly larger. It is the only species of its genus to occur in the New World and is one of the only three New World stork species, together with the wood stork and the jabiru.