American White Pelican
Encyclopedia
The American White Pelican (Pelecanus erythrorhynchos) is a large aquatic
Aquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...

 bird from the order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 Pelecaniformes
Pelecaniformes
The Pelecaniformes is a order of medium-sized and large waterbirds found worldwide. As traditionally—but erroneously—defined, they encompass all birds that have feet with all four toes webbed. Hence, they were formerly also known by such names as totipalmates or steganopodes...

. It breeds in interior North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, moving south and to the coasts, as far as Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

, in winter.

The scientific name means "red-billed pelican", from the Latin term for a pelican
Pelican
A pelican, derived from the Greek word πελεκυς pelekys is a large water bird with a large throat pouch, belonging to the bird family Pelecanidae....

, Pelecanus, and erythrorhynchos, derived from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

 words erythros (ἐρυθρός, "red") + rhynchos (ῥύγχος, "bill").

Description

It is a very large and plump bird; its overall length is about 50–67 in (127–170.2 cm), courtesy of the huge beak which measures 13–14.4 in (330.2–365.8 mm) in males and 10.4–13 in (264.2–330.2 mm) in females. It has a wingspan of about 95–120 in (241.3–304.8 cm). Body weight can range between 10 and 30 lb (4.5 and 13.6 kg), although typically these birds average between 11 and 20 lb (5 and 9.1 kg). The plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...

 is almost entirely bright white, except 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 moult
Moult
In biology, moulting or molting , also known as sloughing, shedding, or for some species, ecdysis, is the manner in which an animal routinely casts off a part of its body , either at specific times of year, or at specific points in its life cycle.Moulting can involve the epidermis , pelage...

ing into the eclipse plumage, the upper head often has a grey hue, as blackish feathers grow between the small wispy white crest.

The bill
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...

 is long and flat, with a large throat sac, and in the breeding season vivid orange like the iris
Iris (anatomy)
The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...

, the bare skin around the eye, and the feet. In the breeding season, there is a lateral
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...

ly flattened "horn" on the upper bill, about one-third the bill's length behind the tip. This is shed off after the birds have mated and laid their eggs, and outside the breeding season the bare parts become duller in color, with the naked facial skin yellow and the bill, pouch and feet an orangy-flesh color.

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. Hatchlings are naked at first, then grow white down feather
Down feather
The down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down. Powder down is a specialized type of down found only in a few groups of birds. Down is a fine thermal insulator and padding, used in goods such as jackets, bedding,...

s all over, before moulting to the immature plumage.

Distribution and ecology

American White Pelicans nest in colonies of several hundred pairs on islands in remote brackish and freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

 lakes of inland North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. The most northerly nesting colony can be found on islands in the rapids of the Slave River
Slave River
The Slave River is a Canadian river that flows from Lake Athabasca in northeastern Alberta and empties into Great Slave Lake in the Northwest Territories....

 between Fort Fitzgerald, Alberta and Fort Smith, Northwest Territories
Fort Smith, Northwest Territories
Fort Smith is a town in the South Slave Region of the Northwest Territories, Canada. It is located in the southeastern portion of the Northwest Territories, on the Slave River and adjacent to the NWT/Alberta border.-History:Fort Smith's history began because of the Slave River and the vital link...

. About 10-20% of the population uses Gunnison Island
Gunnison Island
Gunnison Island is located in the northwest quadrant of the Great Salt Lake in the U.S. State of Utah , approximately 55 miles northwest from Salt Lake City and about 6 miles east from the lake's western shore. Approximately 1 mile long and a half-mile wide, Gunnison Island is best known as an...

 in the Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...

's Great Salt Lake
Great Salt Lake
The Great Salt Lake, located in the northern part of the U.S. state of Utah, is the largest salt water lake in the western hemisphere, the fourth-largest terminal lake in the world. In an average year the lake covers an area of around , but the lake's size fluctuates substantially due to its...

 as a nesting ground. The southernmost colonies are in southwestern Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

 and northeastern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

.

They winter on the Pacific and Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

 coasts from central California and Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

 south to Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

, and along the Mississippi River
Mississippi River
The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...

 at least as far north as St. Louis, Missouri
St. Louis, Missouri
St. Louis is an independent city on the eastern border of Missouri, United States. With a population of 319,294, it was the 58th-largest U.S. city at the 2010 U.S. Census. The Greater St...

. In winter quarters, they are rarely found on the open seashore, preferring estuaries and lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

s. They cross deserts and mountains but avoid the open ocean on migration
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...

. But stray birds, often blown off course by hurricanes, have been seen in the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...

. In Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...

n territory it has been recorded first on February 22, 1997, on the San Andrés Island, where they might have been swept by Hurricane Marco
Hurricane Marco (1996)
Hurricane Marco was a Category 1 hurricane which caused flooding and mudslides in parts of the Caribbean. The 13th named storm of the 1996 Atlantic hurricane season, Marco developed in the southwestern Caribbean between Jamaica and Honduras on November 16. It attained tropical storm strength...

 which passed nearby in November 1996. Since then, there have also been a few observations likely to pertain to this species on the South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

n mainland, e.g. at Calamar.

Wild American White Pelicans may live for more than 16 years. In captivity, the record lifespan stands at over 34 years.

Food and feeding

Unlike the Brown Pelican
Brown Pelican
The Brown Pelican is the smallest of the eight species of pelican, although it is a large bird in nearly every other regard. It is in length, weighs from and has a wingspan from .-Range and habits:...

 (P. occidentalis), the American White Pelican does not dive for its food. Instead it catches its prey while swimming. Each bird eats more than 4 pounds of food a day, mostly fish such as Cypriniformes
Cypriniformes
The Cypriniformes are an order of ray-finned fish, including the carps, minnows, loaches and relatives. This order contains 5-6 families, over 320 genera, and more than 3,250 species, with new species being described every few months or so, and new genera being recognized regularly...

 like Common Carp
Common carp
The Common carp is a widespread freshwater fish of eutrophic waters in lakes and large rivers in Europe and Asia. The wild populations are considered vulnerable to extinction, but the species has also been domesticated and introduced into environments worldwide, and is often considered an invasive...

 (Cyprinus carpio), Lahontan Tui Chub
Tui chub
The Tui chub, Gila bicolor, is a cyprinid fish native to western North America. Widespread in many areas, it is an important food source for other fish, including the cutthroat trout.- Range :...

 (Gila bicolor obesa) and shiners
Shiner (fish)
Shiner is a common name used for any of several kinds of small, usually silvery fish, in particular a number of cyprinids, but also e.g. the Shiner Perch .Cyprinid shiners are:* Eastern shiners, genus Notropis...

, Perciformes
Perciformes
The Perciformes, also called the Percomorphi or Acanthopteri, is one of the largest orders of vertebrates, containing about 40% of all bony fish. Perciformes means perch-like. They belong to the class of ray-finned fish and comprise over 7,000 species found in almost all aquatic environments...

 like Sacramento Perch
Sacramento perch
The Sacramento perch is a sunfish native to the Sacramento–San Joaquin, Pajaro, and Salinas River areas in California but widely introduced throughout the western United States....

 (Archoplites interruptus) or Yellow Perch
Yellow perch
The yellow perch is a species of perch found in the United States and Canada, where it is often referred to by the shortform perch. Yellow perch look similar to the European perch, but are paler and more yellowish, with less red in the fins. They have six to eight dark, vertical bars on their sides...

 (Perca flavescens), Salmoniformes like Rainbow Trout
Rainbow trout
The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....

 (Oncorhynchus mykiss), Siluriformes (catfish), and jackfish
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...

. Other animals eaten by these birds are crayfish
Crayfish
Crayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related...

  and amphibians. Birds nesting on saline lakes, where food is scarce, will travel great distances to better feeding grounds.

American White Pelicans like to come together in groups of a handful of birds or so to feed, as they can thus cooperate and chase 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, sometimes from other pelicans, sometimes from gull
Gull
Gulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...

s.

Reproduction

As noted above, they are colonial breeders, with up to 5,000 pairs per site. The birds arrive on the breeding grounds in March or April; nesting starts between early April and early June. The nest is a shallow depression scraped in the ground, in some twigs, sticks, reeds or similar debris have been gathered. After about one week of courtship and nest-building, the female lays a clutch
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...

 of usually 2 or 3 eggs, sometimes just one, sometimes up to six.

Both parents incubate for about 4 weeks to 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
Crèche (zoology)
The Crèche in zoology refers to care of another's offspring, for instance in a colony. This term is used in the study of bird colonies...

 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.

Predation

Occasionally, these pelican may nest in colonies on isolated islands, which is believed to significantly reduce the likelihood of mammalian predation. Red fox
Red Fox
The red fox is the largest of the true foxes, as well as being the most geographically spread member of the Carnivora, being distributed across the entire northern hemisphere from the Arctic Circle to North Africa, Central America, and the steppes of Asia...

es and coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

s readily predate colonies that they can access, the later being the only known species to hunt adult pelicans (which are too large for most bird predators to subdue). Several gulls have been known to predate pelican eggs and nestlings (including Herring
American Herring Gull
The American Herring Gull or Smithsonian Gull is a large gull which breeds in North America. It is often treated as a subspecies of the European Herring Gull but is now regarded as a separate species by some authorities.Adults are white with gray back and wings, black wingtips with white spots,...

, Ring-billed
Ring-billed Gull
The Ring-billed Gull is a medium-sized gull.Adults are length and with a wingspan. The head, neck and underparts are white; the relatively short bill is yellow with a dark ring; the back and wings are silver gray; and the legs are yellow. The eyes are yellow with red rims...

 and California Gull
California Gull
The California Gull Larus californicus is a medium-sized gull, smaller on average than the Herring Gull but larger on average than the Ring-billed Gull, though may overlap in size greatly with both....

), as well as Common Raven
Common Raven
The Common Raven , also known as the Northern Raven, is a large, all-black passerine bird. Found across the northern hemisphere, it is the most widely distributed of all corvids...

s. Young pelicans may be hunted by Great Horned Owl
Great Horned Owl
The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:...

s and Bald Eagle
Bald Eagle
The Bald Eagle is a bird of prey found in North America. It is the national bird and symbol of the United States of America. This sea eagle has two known sub-species and forms a species pair with the White-tailed Eagle...

s. The pelicans react differently to mammalian threats as opposed to avian threats. Though fairly approachable while feeding, the pelicans may temporarily abandon their nests if a human or other large mammal 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.

Status and conservation

This species is protected by the Migratory Bird Treaty Act of 1918
Migratory Bird Treaty Act of 1918
The Migratory Bird Treaty Act of 1918 , codified at , is a United States federal law, at first enacted in 1916 in order to implement the convention for the protection of migratory birds between the United States and Great Britain...

. It has the California Department of Fish and Game
California Department of Fish and Game
The California Department of Fish and Game is a department within the government of California, falling under its parent California Natural Resources Agency. The Department of Fish and Game manages and protects the state's diverse fish, wildlife, plant resources, and native habitats...

 protective status California Species of Special Concern
California species of special concern
"Species of special concern" is a protective legal designation assigned by the California Department of Fish & Game to wildlife species that are at risk...

 (CSC). On a global scale however, the species is common enough to qualify as a Species of Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...

 according to the IUCN.

Habitat loss is the largest known cause of nesting failure, with flooding and drought
Drought
A drought is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region...

 being recurrent problems. Human-related losses include entanglement in fishing gear, boating
Boating
Boating is the leisurely activity of travelling by boat, or the recreational use of a boat whether powerboats, sailboats, or man-powered vessels , focused on the travel itself, as well as sports activities, such as fishing or water skiing...

 disturbance and poaching
Poaching
Poaching is the illegal taking of wild plants or animals contrary to local and international conservation and wildlife management laws. Violations of hunting laws and regulations are normally punishable by law and, collectively, such violations are known as poaching.It may be illegal and in...

 as well as additional habitat degradation.

There was a pronounced decline in American White Pelican numbers in the mid-20th century, attributable to the excessive spraying of DDT
DDT
DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....

, endrin
Endrin
Endrin is an organochloride that was primarily used as an insecticide. It is a colourless odorless solid, although commercial samples are often off-white. It is also a rodenticide. This compound became infamous as persistent organic pollutant and for this reason is banned in many...

 and other organochloride
Organochloride
An organochloride, organochlorine, chlorocarbon, chlorinated hydrocarbon, or chlorinated solvent is an organic compound containing at least one covalently bonded chlorine atom. Their wide structural variety and divergent chemical properties lead to a broad range of applications...

s in agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

 as well as widespread draining and pollution of wetlands. But populations have recovered well after stricter environmental protection
Environmental protection
Environmental protection is a practice of protecting the environment, on individual, organizational or governmental level, for the benefit of the natural environment and humans. Due to the pressures of population and our technology the biophysical environment is being degraded, sometimes permanently...

 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
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, and 18,500 nests in the 14-17 United States colonies. Shoreline erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

 at breeding colonies remains a problem in some cases, as are the occasional mass poisonings when pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...

s are used near breeding or wintering sites.

External links

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