Pelecanus erythrorhynchos

American white pelicans are found throughout North America. They breed in inland, prairie regions of the United States and Canada and winter in southern and coastal areas. Breeding occurs in suitable habitat from British Columbia, Alberta, Saskatchewan, Manitoba, and southwestern Ontario south through northern California, Nevada, and Colorado. They winter in southern California, coastal and eastern Mexico, the coastal plain of Texas, and throughout the Gulf states, including Florida. Populations that breed mostly east of the continental divide tend to migrate to winter ranges in the Gulf of Mexico, breeding populations west of the continental divide tend to migrate towards Baja California and western Mexico. There are several, small year-round populations along the Gulf of Mexico and in central Durango, Mexico. The winter range is characterized by minimum January temperatures above 4 degrees Celsius.

Biogeographic Regions: nearctic (Native )

S Canada to s US; winters to Costa Rica.

Caribbean; North America

Gulf of Maine, Gulf of Mexico, North America, North West Atlantic

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Breeding

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (200,000-2,500,000 square km (about 80,000-1,000,000 square miles)) Nesting occurs locally in south-central British Columbia, Alberta, Saskatchewan, Manitoba, and southwestern Ontario south through northern California, Nevada, Utah, Colorado, South Dakota, and Minnesota; also on the central coast of Texas and sporadically in east-central Mexico (Tamaulipas) and central Durango, Mexico (Johnsgard 1993, Knopf and Evans 2004). During the nonbreeding season the range includes Florida, Gulf of Mexico coast south to northern Yucatan Peninsula, and central California south to southern Baja California and through western mainland Mexico to Nicaragua (AOU 1983, Knopf and Evans 2004). In North America, the highest winter density occurs in southern Texas (Root 1988); other important areas include the Gulf coast and Everglades region of Florida. In summer, white pelicans sometimes wander north of the usual range.

Coded range extent refers to breeding range.

American white pelicans are large, white pelicans, there are no similar species in North America. Their primary and outer secondary feathers are black, their bill and gular pouch are flesh colored or yellow, and their legs are pale yellow to bright orange. They have a flattened protuberance on the upper bill. American white pelicans are from 127 to 165 cm in length. The other North American pelican species, brown pelicans, are smaller, with dark plumage. Males are slightly larger than females. Their wingspan is from 244 to 290 and reported masses are from 4.54 to 9 kg. There are no described subspecies or geographic variation.

Range mass: 4.54 to 9 kg.

Range length: 127 to 165 cm.

Range wingspan: 244 to 290 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Length: 158 cm

Weight: 7500 grams

Systems

• Terrestrial
• Freshwater
• Marine

American white pelicans winter in coastal areas, such as coastal bays and estuaries. Significant inland wintering areas are the Salton Sea in California and large rivers in areas where water flow prevents freezing. They breed on islands in or near shallow, inland lakes, rivers, and marshes. Islands can be either permanent islands in freshwater water bodies or temporary islands in wetlands. These temporary nesting and roosting habitats can be important in determining breeding and winter distribution. Breeding islands are commonly more than 50 km from areas used for foraging. American white pelicans migrate over inland areas with large lakes and rivers for resting and foraging.

Habitat Regions: temperate ; tropical ; saltwater or marine ; freshwater

Aquatic Biomes: lakes and ponds; rivers and streams; coastal ; brackish water

Wetlands: marsh

Other Habitat Features: estuarine

Depth range based on 7 specimens in 1 taxon.
Water temperature and chemistry ranges based on 1 sample.

Environmental ranges
  Depth range (m): 0 - 0
  Temperature range (°C): 16.316 - 16.316
  Nitrate (umol/L): 0.240 - 0.240
  Salinity (PPS): 33.496 - 33.496
  Oxygen (ml/l): 5.685 - 5.685
  Phosphate (umol/l): 0.330 - 0.330
  Silicate (umol/l): 1.436 - 1.436
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Comments: Habitat includes rivers, lakes, reservoirs, estuaries, bays, and open marshes, sometimes inshore marine habitats. Pelicans rest/roost on islands and peninsulas. Nests usually are on islands or peninsulas (natural or dredge spoils) in brackish or freshwater lakes, or on ephemeral islands in shallower wetlands as in the northern Great Plains or on the Texas coast (knopf and Evans 2004). Eggs are laid on the ground in a slight depression or on a mound of earth and debris 24-36 inches across, 15-20 inches high (Terres 1980), usually on low flat, or gently sloping terrain. Nest sites usually are in open areas but often near vegetation, driftwood, or large rocks (Spendelow and Patton 1988). Habitats used in winter are mainly coastal but also include also inland waters such as the Salton Sea and some rivers with open water (Knopf and Evans 2004). Suitable sand bars and similar sites for roosting or loafing are important components of winter habitat (Knopf and Evans 2004).

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

Most are long-distance migrants; resident along Gulf coast of Texas and Tamaulipas (Johnsgard 1993). Migration corridors are mostly inland. Winter range of breeders from North Dakota and Saskatchewan includes the western Gulf coast; some birds from Saskatchewan have been recovered on the Pacific coast of Mexico and El Salvador; most breeders from western Wyoming, Utah, Nevada, and British Columbia winter in California and western Mexico (see Johnsgard 1993).

Maximum distance between nesting site and breeding season foraging area can be 100 to 300 kilometers (Low et al. 1950, Marshall and Giles 1953, Lingle and Sloan 1980; also see Johnsgard 1993).

American white pelicans forage in shallow waters for fish, crustaceans, and amphibians. They may also forage in deeper waters where fish occur near the surface. They forage during the day typically, but may forage at night during the breeding season. They forage alone or in cooperative groups, they dip their bills into the water while swimming at the surface and scoop prey into their bill and gular pouch. Cooperative foraging groups may collaborate to drive prey into shallow waters to make it more difficult for them to escape capture. Individuals that forage in groups tend to have greater foraging success. Plunge-diving, as in brown pelicans, has only been rarely observed in these pelicans. They will also take prey from other pelicans or waterbirds, including double-crested cormorants, gulls, and other pelicans. American white pelicans eat mainly small, schooling fish, although they also eat crayfish and amphibians on inland lakes and rivers in the breeding season. Fish recorded in the diet include carp, minnows, tui chub, and occasionally game fish, such as salmon.

Animal Foods: amphibians; fish; aquatic crustaceans

Primary Diet: carnivore (Piscivore )

Comments: Diet includes mainly fishes of little commercial value (e.g., carp, perch, catfish, suckers, sticklebacks, minnows) (Terres 1980), also locally trout, centrarchids, tiger salamanders, or crayfishes. Locally, tiger salamanders may be important as food for chicks. Foraging often occurs in shallow water. Pelicans sometimes forage cooperatively, forming a semicircle and herding fishes.

American white pelicans often breed in colonies along with double-crested cormorants, gull species, Canada geese, great blue herons, common terns, and Caspian terns.

American white pelicans suffer from infestations of biting lice (Piagetiella peralis), especially around their mouth and gular pouch. Nematodes (Contracaecum spiculigerum) and tape worms (tape worms Hymenolepis species, Dibothrium cordiceps, Oilgorchis longivaginatus) have been reported from guts. One individual was infested with subcutaneous mites (Pelecanectes apunctatus).

Commensal/Parasitic Species:

• biting lice (Piagetiella peralis)
• nematodes (Contracaecum spiculigerum)
• tape worms (Hymenolepis species)
• tape worms (Dibothrium cordiceps)
• tape worms (Oilgorchis longivaginatus)
• subcutaneous mites (Pelecanectes apunctatus)

Breeding colonies on isolated islands help to lessen the threat of terrestrial predators on American white pelican young and eggs. Red foxes and coyotes are threats to breeding colonies that are accessible. Gull species prey on eggs and young, including herring gulls, California gulls, and ring-billed gulls. Also, common ravens prey on eggs and great horned owls and bald eagles take young. Adult size may lessen the risk of predation, but coyotes have been known to take adults. Although American white pelicans readily forage and loaf near humans, they are easily disturbed from nests, abandoning their young readily when a threat is perceived. Gulls take advantage of this to attack exposed nestlings. They also attack nestlings that have wandered from the nest or been expelled by an older sibling. Gulls also take food from young if they empty their stomach contents after being disturbed. These pelicans don't leave the nest in response to avian predators, instead jabbing at them with their bills.

Known Predators:

• red foxes (Vulpes vulpes)
• coyotes (Canis latrans)
• herring gulls (Larus argentatus)
• California gulls (Larus californicus)
• ring-billed gulls (Larus delawarensis)
• common ravens (Corvus corax)
• great horned owls (Bubo virginianus)
• bald eagles (Haliaeetus leucocephalus)

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 21 - 80

Comments: Breeding occurrences include at least 27 colonies east of the Continental Divide and 15 west of the Divide; several additional colonies likely exist but have not been recently documented (King and Anderson 2005).

100,000 - 1,000,000 individuals

Comments: Using available data (1998-2001), King and Anderson (2005) determined that at least 27 American white pelican colonies and 48,240 nests occur east of the Continental Divide and at least 15 colonies and 18,790 nests exist west of the Divide, for a total of about 134,000 breeding pelicans in North America. However, many pelican colonies have not been surveyed since the early 1980s, and these figures do not include several colonies in Canada, the United States, and Mexico. Population size in 1995, including nonbreeders, was estimated at 400,000 (Keith 2005). The largest colony (34,000 breeders in 2002) is at Chase Lake, North Dakota (Sovoda et al. 2005).

Gregarious. Significant predators at various breeding sites include gulls, coyotes, and probably large corvids and other mammals.

Adult American white pelicans are relatively silent, only using low grunts when in aggressive or sexual interactions. Young pelicans squawk loudly to beg for food. American white pelicans use a variety of visual displays to communicate aggression, appeasement, and alarm. They will jab at others with their bill or extend their gaped mouth towards them, usually in aggressive interactions around territories or mating. They hold their head upright with the bill extended horizontally and the gular pouch expanded, accompanied by a grunt, as a greeting or mild threat. In flight over colonies they stop flapping briefly and hold the bill down as another mild threat. Crouching or bowing is an appeasement display in young and adults. Courtship includes several visual displays in the air and on the ground, including circular courtship flights above the colony, parallel strutting displays between pairs, bowing, and head swaying between mates at the nest.

Communication Channels: visual ; acoustic

Comments: Feeding activity generally peaks in morning and late afternoon or evening. In some areas, foraging occurs at night as well as diurnally (McMahon and Evans 1992).

American white pelicans typically successfully raise just 1 of the 2 eggs they lay. Only 9.7% of clutches in one colony successfully raised 2 young to fledgling. Average mortality of that offspring through its first year of life is 41%. Average mortality from the 1st to 2nd year is 16%, and average mortality drops after that. The oldest recorded American white pelican in the wild was 26.4 years old. Nestlings and eggs die as a result of rolling out of nests, nest abandonment, starvation, attacks by other pelicans in the nesting colony, exposure, and predation. Adults are killed by severe weather, hitting wires, and diseases such as botulism.

Range lifespan
Status: wild: 26.4 (high) years.

Maximum longevity: 54 years (wild)

American white pelicans form monogamous pairs in breeding season and defend small nesting territories in breeding colonies. Pair bonds form on arrival at the breeding colony through courtship rituals. These courtship displays include a circular courtship flight, parallel strutting walks, head swaying, and bowing. Bonds last through most of the breeding season, but whether pairs reform in subsequent years is unknown. Males guard female mates, although extra-pair copulations seem rare.

Mating System: monogamous

Once the bulk of birds arrive on the breeding grounds, pairs begin to form and breed. Mating occurs from late March through early May. Once a pair has formed, they begin to establish and defend a nest scrape. This process is highly synchronous in colonies, with nests being established over the course of about a week. Nests are simple scrapes with low rims on bare, level ground that are accessible to flying pelicans. Nest sites typically have little vegetation, but may be among low shrubs, weeds, or grass. They have 1 brood each year, laying 2 chalky-white eggs 2 days apart. If an egg is lost, it is not replaced. If both are lost, the nest is deserted. Eggs are incubated continuously under the foot webs of parents for about 30 days and brooded for about 17 days further. Young are fed by regurgitation by parents until the young leaves the colony at fledging, usually at 10 to 11 weeks after hatching. American white pelicans begin breeding at 3 years old.

Breeding interval: American white pelicans breed once yearly.

Breeding season: Breeding occurs from late March through early May.

Range eggs per season: 1 to 2.

Average eggs per season: 2.

Average time to hatching: 30 days.

Range fledging age: 10 to 11 weeks.

Average time to independence: 3 years.

Average age at sexual or reproductive maturity (female): 3 years.

Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

Both parents incubate eggs, taking turns every 72 hours. When brooding, parents exchange places about every day.

Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male, Female); pre-weaning/fledging (Protecting: Male, Female)

Egg laying occurs May-July in Texas, late April-June (mainly before June) in Utah. In Canada, nesting begins in May or June; hatching in the first nests sometimes precedes initiation of the last clutches. In Manitoba, flocks first flew over colony sites 34-38 days before hatching. Clutch size is commonly 2, but pairs rarely fledge more than one young. Incubation, by both adults, averages 31-32 days, Young are tended by adults, leave nest in about 21-28 days, join other young in group, fledge at 9-10 weeks, and attain sexual maturity usually at 3 years. Mortality of eggs and chicks generally is high. Female generally does not renest following clutch loss.

The following is a representative barcode sequence, the centroid of all available sequences for this species.

There are 4 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 4
Specimens with Barcodes: 6
Species With Barcodes: 1

Canada

Rounded National Status Rank: N3B - Vulnerable

United States

Rounded National Status Rank: N4 - Apparently Secure

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 2008
  Least Concern
• 2004
  Least Concern

There have been documented increases in American white pelican populations in recent years, resulting from conservation efforts. Historically populations declined in response to destruction of breeding and foraging habitats and continued destruction of wetland habitats remains one of the most important influences on current populations. American white pelicans are especially sensitive to human disturbance at nesting sites, where human presence can result in temporary or permanent nest abandonment, increasing the likelihood of mortality associated with exposure and gull predation. Common human disturbances at nesting colonies are low-flying airplanes or motorboats. Pesticide use throughout their range has resulted in egg-shell thinning and poisoning. They are considered least concern by the IUCN because of their large population sizes and broad range.

US Migratory Bird Act: protected

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

Rounded Global Status Rank: G4 - Apparently Secure

Reasons: Large nesting and winter range in Canada, United States, and Mexico; several dozen colonies include more than 60,000 nesting pairs; population has increased greatly since the 1960s; highly vulnerable to disturbance; habitat protection remains a concern, as does increased incidence and severity of disease.

Population

Global Short Term Trend: Increase of 10 to >25%

Comments: The number of nesting pairs in 20 colonies that were surveyed during 1979-81 and again in 1998-2001 more than doubled during that approximately 20-year time interval (King and Anderson 2005).

Breeding Bird Survey data indicate that the continental population increasied steadily and rapidly at rate of 3.9 percent per year from 1980 through 2003 (Knopf and Evans 2004).

Global Long Term Trend: Decline of 30-70%

Comments: Severe declines occurred historically (King and Anderson 2005, Murphy 2005), but the magnitude of the difference between the former population size and current population size is uncertain.

West of the Continental Divide, the number of breeding colonies declined from 23-24 in the early 1900s 5-8 in 1984 (King and Anderson 2005). Several colonies of unknown but likely large size in California disappeared in the 1900s before breeding numbers had been documented (Shuford 2005). At the same time, new colonies became established (e.g., in Montana and British Columbia).

Population size declined through the 1960s and increased greatly through the early 2000s.

Degree of Threat: Medium

Comments: This species is highly sensitive to human intrusion into breeding colonies, which cause desertions and exposure of eggs and young to temperature extremes and gull predation (Knopf and Evans 2004). Loud and close passes by motor boats and low flying airplanes can cause bird to flee from nesting colonies or feeding or roosting areas (Knopf and Evans 2004).

Hydrological alterations by humans have resulted in a net loss of breeding and feeding areas (Murphy 2005), and these alterations remain an important potential limiting factor (Knopf and Evans 2004). Some hydrological changes have created or improved nesting habitat.

Diseases (particularly Type C botulism and West Nile virus) have caused significant die-offs and mortality in recent years and are a cause for concern (Rocke et al. 2005).

In some areas, pelicans fly long distances (hundreds of kilometers) from nesting areas to the closest suitable feeding areas, but may nevertheless breed successfully.

Ehrlich et al. (1992) noted that several nesting colonies were jeopardized by several consecutive years of drought, which may lower water levels and allow mammal predators (particularly coyote and raccoon) access to pelican breeding sites.

Shooting historically was a significant mortality factor and still is the greatest mortality factor resulting in band returns (Evans and Knopf 1993).

After the 1960s, hundreds of pelicans died yearly due to the ingestion of insecticides such as toxaphene, endrin, and dieldrin, and as recently as winter 1998-99, 800 American white pelicans died in Florida from poisoning by insecticides that were resuspended from flooded agricultural soils (Keith 2005). However, pesticides and mercury currently are not regarded as significant causes of reproductive failure or population decline (see Knopf and Evans 2004). However, there is concern that increased incidence and severity of disease in pelicans may be related to pesticide contamination (Murphy 2005).

Management Requirements: Maintain water levels where birds nest and forage. Limit or restrict access to breeding colonies especially during courtship and early incubation. Prevent shooting. Restrict pesticide usage.

Biological Research Needs: The relationship between pesticide contamination and vulnerability to disease needs to be investigated (Murphy 2005). Better information is needed on demographics and metapopulation dynamics.

Global Protection: Many to very many (13 to >40) occurrences appropriately protected and managed

Comments: Many nesting colonies are in protected areas. At least 13 colonies in the United States are in national parks or state or federal wildlife refuges; all colonies in Saskatchewan are designated wildlife refuges; Alberta prohibits approach within 0.5 miles or entry into 6 colonies from 15 Apr to 15 Sept (Sidle et al. 1985).

Needs: The larger colonies (500+ nests) should be protected. Some nesting areas need protection against incursion by coyotes and raccoons; predator exclusion fences have been used successfully (Madden and Restani 2005)..

There are no known adverse effects of American white pelicans on humans. They were previously persecuted because of the misperception that they compete with humans for fish prey, but American white pelicans eat mainly small fish with no commercial value.

American white pelicans are lovely, majestic birds that are appreciate by bird enthusiasts. Historically they were also hunted for sport.