Brown Pelicans

brown pelican in flight in Bodega Bay, California

Brown pelicans (Scientific name: Pelecanus occidentalis) are native to North and South America and are found in warm, shallow waters throughout the nearctic and neotropical regions of both the Pacific and Atlantic oceans. Although considered strictly coastal, there are some records of brown pelicans in urban areas and living inland during the post-breeding season. In the U.S. brown pelicans breed in 10 coastal states in the U.S.: Maryland, Virginia, North Carolina, South Carolina, Georgia, Florida, Louisiana, Alabama, Texas, and California. In Mexico, they are found on offshore islands, and coastal areas along the Caribbean and along the Gulf of Mexico. They have been observed on the Pacific coasts in Honduras, Costa Rica, Belize, and Panama and in the West Indies in Cuba, Jamaica, Dominican Republic, Puerto Rico, U.S. Virgin Islands, British Virgin Islands, Aruba, Barbuda, and Antigua. Among the places they have been seen South American are the Caribbean coast of Colombia, Venezuela and the Galapagos Island. The only colony on the Pacific coast in South America is in Ecuador. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

Pelicans are rarely found more than 32 kilometers (20 miles) from the shoreline. They are found in warm coastal waters or marine estuaries, wetlands, marshes and swamps and and estuaries. /=\ during the non-breeding season. They require dry areas that are not subjected to frequent disturbance. They roost offshore at night and loaf (rest) during the day after or while foraging. Typical loaf and roost sites include sandbars, pilings, jetties, breakwaters, mangrove islets, and offshore rocks or islands. To breed, they move to small, predator-free islands. On the Atlantic and Gulf Coasts, brown pelicans are found breeding on barrier islands, natural estuarine islands, or dredge-spoil islands. Along the Pacific Coast and the northern Gulf of California they breed on dry, rocky islands. In mainland Mexico, they are found in mangroves. In the tropics, they inhabit coastal and inland mangroves and humid forests. /=\

Brown pelicans are not endangered. They are designated as a species of least concern on the International Union for Conservation of Nature (IUCN) Red List and have no special status according to the Convention on International Trade in Endangered Species (CITES). Brown pelicans were listed as endangered in 1970 after they were pushed nearly to extinction by DDT, which thinned their eggshells. They were taken off the list in 2009 and now number about 150,000 along the West Coast.

Brown pelicans have a long lifespan. The oldest one ever recorded in the wild was 43 years of age. About 30 percent of brown pelicans survive past the first year, and less than two percent survive longer than 10 years. In one survey, three banded birds survived past the 20 year mark, reaching at 31, 37, and 43 years old. However these data may be incomplete because bands may corrode and fall off after 12 to 15 years.

Websites and Resources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Encyclopedia of Life eol.org; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; MarineBio marinebio.org/oceans/creatures

Brown Pelican Characteristics

range of the brown pelican

Brown pelicans are large birds. They range in weight from two to five kilograms (4.4 to 11 pounds) and range in length from 1 to 1.4 meters (3.3 to 4.5 feet). Their average wingspan is two meters (6.6 feet). Males are larger than females. They are typically 15 to 20 percent heavier than females. Their bill that ranges from 25 to 38 centimeters (0.8 to 1.25 feet) in length (10 percent longer in males than females). The male wingspan is three to six percent longer in males than females. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

Brown pelicans are easily distinguished by their long bill, and very large gular pouch. They are the darkest plumed of the pelicans. According to Animal Diversity Web: They have feet with webbing that stretches from the front to the hind toe. Their gular pouch is able to hold up to three gallons of water, which is three times more than what the stomach can hold. The distal portion of the gular pouch is a dark gray-green year round and during mating, the proximal area of the gular pouch turns a bright red. During incubation, the proximal area of the pouch turns back to the normal gray-green color. /=\

During post-breeding season the head becomes pale yellow and the neck becomes white. Immediately prior to breeding the head becomes yellow but the neck turns a dark brown color. During the nesting period, the head turns white with randomly-placed dark feathers and a brown neck. The plumage in males and females is similar except that females are likely to molt before males (females molt at 34 to 36 months; males at 36 to 40 months). /=\

Juvenile brown pelicans display a brown iris which changes to a light tan or blue during courtship. After onset of incubation, the iris returns to a dark brown color. Additionally, juveniles display a black eye ring until 16 to 19 months, at which point it turns pale blue-black color. In adults, this eye ring is a gray-pink most of the year, changes to pink during mating, and then darkens to brown following onset of incubation. /=\

Brown pelicans are able to drink saltwater due to the salt gland that is unique to birds (although non-functional and smaller in birds that are not exposed to high salinity) which excretes excess salt. These glands are located on the anterior sides of the eyes and are 2.6 to 3 centimeters (1.1 to 1.3 inches) in length and 0.6 to 0.8 centimeters in width. These glands are necessary because the kidney is only able to rid the body of half the salt ingested. These glands are able to excrete salt in such high concentrations that it makes the drinking of saltwater tolerable and aids in conservation of water. /=\

Brown Pelican Behavior and Communication

Brown pelican
Brown pelicans are terricolous (living in the ground) when on land, good gliders, diurnal (active during the daytime), crepuscular (active at dawn and dusk), motile (move around as opposed to being stationary), migratory (make seasonal movements between regions, such as between breeding and wintering grounds), territorial (defend an area within the home range) and colonial (living together in groups or in close proximity to each other). In terms of home range, brown pelicans forage within 20 kilometers of their nesting site during the breeding season. During the non-breeding season they forage up to 175 kilometers from the mainland and 75 kilometers from an island. They have been observed foraging at night during full moons. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

According to Animal Diversity Web: A 1986 study monitored a brown pelican via a transmitter for 68.8 daylight hours. The bird spent 32 percent of this time active and 68 percent inactive. It was never active at night, minimally active during twilight hours, and most active during daylight hours. Brown pelicans sleep on land either standing on both feet, or resting on their breast and belly, with their head on their shoulder and their bill tilted towards the side. When sunbathing, they usually spread one wing to the side, and rarely both. When bathing, they plunge their head below the surface, spreading their wings and beating their wings against the water's surface. After bathing, brown pelicans use their bills to spread oil secreted by the uropygial gland onto their feathers. /=\

Brown pelicans are territorial of their nesting area. Threat displays include head swaying, which indicates readiness to interact. Defensive displays, often done when another pelican comes too close to the nest, include bowing followed by a "hrraa-hrraa" sound. Brown pelicans will avoid physical confrontation by displays of head swaying or raising their bill horizontally while spreading their wings. Play behaviors have been observed in nestlings, such as dismantling the nest or throwing sticks or shells into the air then retrieving them. Brown pelicans will defend their nest if intruders enter, often killing young pelicans who come too close./=\

Brown pelicans in northern ranges migrate south in autumn, returning during the months of March and April. The cold weather and decreased availability of surface prey induce migration. Small populations of brown pelicans do remain in the northern ranges during the the winter months. Thousands have been documented in North and South Carolina. Those flocks in warmer climates typically will not migrate./=\

Brown pelicans sense using vision, touch, sound and chemicals usually detected with smell and communicate with vision, touch, sound and chemicals usually detected by smelling. Adult brown pelicans communicate, particularly during mate selection and nest site protection, with a low "hrraa-hrraa" sound and head swaying. Other interactions include bowing, which is usually more of a defensive behavior. Non-aggressive behaviors include swinging of head side to side, raising of bill horizontally and spreading wings outward, and cleaning the opposite side of the nearby pelican. Peeps from eggs can be heard up to two days prior to the start of hatching. Nestlings release a high pitched, scratchy call to their parents usually while the parents are searching for food. /=\

Brown Pelican Flying, Diving and Feeding

brown pelican diving

Brown pelicans are carnivores, primarily feeding on fish but also small marine invertebrates. They are the only pelicans that dive for food. They catch fish and other sea creatures by folding their wings in flight and plunging into the water at speeds up to 64 kilometers per hour (40 mph). Diving is their primary means of obtaining food. Their superb eyesight while in flight allows them to dive from up to 20 meters in the air. Although their eyesight is poor underwater, they can often be observed floating and feeding by surface-seizing with success. The lower jaw is split into two halves which turn out upon impact with the water's surface, forming a scoop with the gular pouch.

According to Animal Diversity Web: Brown pelicans “have air sacs which allow them to be very buoyant in the water. They never swim below the surface but will plunge their head below it in an attempt to catch prey. They paddle their webbed feet to move around on the water's surface. On land they tend to be clumsy and can use their wings for better balance by extending them outwards. In the air they alternate between gliding and flapping, with an average flap rate of 2.4 beats between gliding intervals. They glide just above the water's surface to decrease drag at an average speed of 11.7 meters per second. During takeoff they extend their necks, and then pull their head back onto the shoulders once in flight. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

Most are observed foraging is close to shore but there are records of them diving up to 32 kilometers (20 miles) offshore. They are typically solitary while foraging, but if two or more forage together they will feed in sequence, driving fish towards the other(s). Foraging is most commonly observed in early morning and evening and occasionally at night during a full moon. Florida pelicans forage on small fish and some marine invertebrates in shallow waters, typically in water less than 150 meters deep.

In the Virgin Islands, herring and fry fish are often fish of choice after being driven to the surface by other predatory fish such as sharks, salmon, and dolphins. From Cuba to Bermuda, stomach contents have shown herring, anchovies, sardines, and fry of these fish are consumed most frequently. Begging and scavenging at piers, docks, and boats can yield a fair amount of food for birds that have access to them. Laughing gulls often steal food from pelicans’ beaks, sometimes perching on their backs and waiting for the opportunity. Although rare, brown pelicans have been observed stealing fish from the beaks of other birds as well. /=\

Not surprisingly, adult pelicans are more successful hunters than younger birds. A study in Southwest Mexico found that adult pelicans are successful 84 percent of time compared to only 75 percent of the time in juveniles. An even greater discrepancy was seen in a study done in Belize; adults were successful 83 percent of the time where juveniles only had a success rate of 43 percent. These differences in feeding success could be attributed to diving and prey-handling skills, patch choice, knowledge of appropriate dive heights, angles, and ability to determine likelihood of success. Adult birds were seen "wheeling" in the air but if chance of successful foraging was determined to be low they would continue flying. Juveniles would always dive after a "wheel" regardless of interpreted success, therefore wasting more energy when not successful. A study done in Florida showed a linear correlation between age of the brown pelican and success rate: pelicans less than one year old had 4 percent success rate, 12 to 22 month old pelicans had a eight percent success rate, 22 to 40 month old pelicans had a 12 percent success rate, and adults older than 36 months had a success rate of 14 percent. /=\

Brown Pelican Breeding and Reproduction

brown pelican juvenile

Brown pelicans engage in seasonal breeding and year-round breeding. They breed seasonally in colder climates and year-round in warmer climates. The number of eggs laid each season ranges from two to three. The average number of eggs per season is two or three. The average time to hatching is 30 days. The average fledging age is 11 weeks and the average time to independence is three months. Females and males reach sexual maturity at two to 4 years. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

Brown pelicans nest in irregular patterns. They migrate to 20 to 30 degrees north latitude to breed if they do not live in this range year-round. Nesting lasts throughout the year in certain tropical regions, but generally begins in late fall and lasts into early June. Those which nest between 20 and 30 degrees north latitude nest more regularly through winter into spring. However, those which nest 30 to 35 degrees north of the equator nest definitively in the spring and summer seasons.

The breeding season varies with latitude and often depends on local food availability. According to Animal Diversity Web. In Maryland, they begin to lay eggs in late May through early September with peaks of egg laying varying between years. In North Carolina, the laying season is mid-March through July. In Florida, egg laying periods vary from east to west coasts; egg laying is December to June on the Atlantic coast and January to June on the Gulf side. In Louisiana, the egg laying season was March to June up until the near extinction of the pelican population in this area. The new population now begins either in December or January and ends in June. Texas populations begin in March and last through June, with egg output peaking in April through May. In south California, egg laying starts in December, lasts until early August and peaks between February and May. In the Gulf of California, egg laying is November until May. In Panama, egg laying lasts from January until May. In west and southwest Puerto Rico, breeding peaks between September and November but in eastern Puerto Rico, brown pelicans breed year-round. In Venezuela, the breeding season is from November to June, peaking between January and February. In the U.S. Virgin Islands, as well as the Galapagos Islands, breeding is year-round. /=\

Brown pelicans are seasonally monogamous. Males select a nest site prior to courtship and pair bond formation. Males protect a potential nest area and nearby perches for up to three weeks. Males initiate courtship rituals but both males and females participate. Rituals include head swaying, bowing, and turning. Both sexes also release a "low raaa" call. Courtship typically lasts two to four days before pair bonding occurs, but can last up to 21 days. As part of the pair bonding and nest building ritual, males present females with nesting materials. Building the nest can take up to seven days. The first egg is laid three days after the completion of the nest. /=\

Copulation occurs about seven times before the first egg is laid and each act lasts seven to 14 seconds. During copulation, the male grabs the female's upper neck with his bill, mounts her from behind, and holds her neck in this way until the act is over. The female is passive except for movements of her tail from side to side. Males perform a post mounting display by holding their bill open with their head set back upon the shoulders. Sometimes males will put on displays including bill throws and glottis exposure. /=\

Brown Pelican Nesting

brown pelican nesting on an island in the Chesapeake Bay

Brown pelican nesting is controlled by a variety of factors including: time to nest successfully, molt length, day length fluctuations, food abundance, time when freezing temperatures occur, and timing of hurricane season. Local environmental conditions are the main factor in determining nesting seasons. Sites are used annually until changes in nesting habitat, food availability, or human disturbances induce colony relocation. Breeding locations are ideally within 30 to 50 kilometers of a consistent food supply. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

Parental care is provided by both females and males. Pre-birth protection, is provided by males and females. During the pre-weaning and the pre-independence stages provisioning and protecting are done by females and males. Both males and females work together to build the nest, incubate the eggs and protect the nest. According to Animal Diversity Web: After courtship, pairs build nests in trees or on the ground, and stay in colonies. The optimal spot for ground nests is in medium-density vegetation one to two meters off the ground. This location allows their offspring to leave the nest earlier than those in trees, some as early as three weeks old. The most ideal location for a nest in a tree is a spot with nearby branches adequate for landing and taking off. Male brown pelicans bring the nest-building materials while females build the nests. Material is dependent on what is available at the nest site. Ground nests can be as simple as a shallow depression in the sands lined with grass or as complex as a full structure built out of sticks, grass stems, and seaweed. Nests in trees are typically made up of sticks, grass, or leaves. Males have been documented stealing from unattended nests as well as using man-made materials such as rope or window screening. Males will continue to bring the female building materials during incubation and until juveniles reach fledgling age./=\

Eggs have a textured surface and are chalky white in color. The number of eggs laid ranges from one to four. Adult brown pelicans lay three eggs per season on average, while juvenile pelicans less than three years old lay no more than two eggs. Pelicans incubate eggs with their webbed feet. Both parents share responsibility for turning and incubating the eggs as well as protecting them from predation. The incubation period typically lasts 29 to 32 days and only about 70 percent of eggs laid in a season will hatch. Eggs are laid in 24 to 64 hour intervals but will still hatch within one day of one another. Brown pelicans in captivity have laid eggs to replace those lost during the nesting season. /=\

Brown Pelican Young and Development

According to Animal Diversity Web: Brown pelican chicks have a have an egg-tooth on the tip of their beak which they use on the broadest part of the egg to break open the shell. After the initial peck, it usually takes 31 hours for the chicks to fully hatch. Initial weight of brown pelican chicks ranges from 54.9 to 87 grams with an average weight of 73.5 grams. Ten grams of this weight is egg yolk withheld in the abdomen. The egg tooth disappears within 10 days of hatching. [Source: Victoria Scott, Animal Diversity Web (ADW) /=]

Both males and females work together to feed and protect the young, and teach the offspring how to fly. Parents alternate guarding the nest until the offspring are 4 to six weeks old. Hatched nestlings have been frequently recorded killing younger siblings either by directly pecking them on head or pushing them from nest, as well as indirectly by not allowing them to feed. The first hatched chick has a survival rate of 70 percent and one study found that up to 30 percent of nestlings in one breeding season were killed by the older sibling. /=\

The young are fed through regurgitation of pre-digested fish onto the nest floor and as much as 50 kilograms of fish is consumed from the hatchling to fledgling stage when raised in captivity. Although no comparable data has been collected on wild brown pelicans, captive adult pelicans have been recorded requiring 0.3 kilograms of fish per day during the summer months and 0.8 kilograms of fish per day during the winter months. /=\

Nestlings are ectothermic (“cold blooded”, use heat from the environment and adapt their behavior to regulate body temperature), at birth and rely on their parents to maintain internal temperature. The development of endothermy begins with increased mass, changes in metabolic rates, and an increase in downy feathers. Initially young brown pelicans feed by pecking regurgitated fish off the nest floor, but as coordination increases, they begin to feed directly from their parents' mouths. After the first 4 to six weeks, parents spend less time in the nest and mostly return to feed their young. At five to six weeks, the parents no longer roost in the nest at night, but rather on nearby perches. Parents feed the young until 11 to 12 weeks of age, when the young reach the fledgling stage. /=\

Newly hatched chicks have pinkish gray skin covered in fluff. On postnatal day 9, the chicks' skin has darkened. By day 10, they are lightly covered in a layer of white down which is fully developed by day 20. The legs and feet of brown pelicans less than 24 days old are a dull white color. This quickly changes to a dark grey or black when they are juveniles and into adulthood. Juvenile feathers appear at day 30 and these are kept until adult feathers develop by age 3. They fledge at 11 weeks and are considered independent at three months. At this time, they abandon the nest but stay within the vicinity of their birth site. A study found that after forced relocation, most returned to their birth site within three years. Those which did not return founded new colonies instead of joining existing ones. Variation in the choice to return or not seemed dependent on food availability and suitable locations for nesting. These nesting areas need to be dry due to the fact that pelicans cannot be directly exposed to water for over an hour without becoming waterlogged. Brown pelicans can mate as young as two but the average is three to 4 years old./=\

During the first year, the underside is white and molt cycles are so rapid that definitive colors are not easily defined per molt. At around 10 weeks, molting starts and juvenile pelicans undergo six molts before reaching definitive basic plumage which then is slightly altered during breeding season. Around three to five years, plumage has developed, the upper areas turn gray to gray-brown, the abdomen turns a blackish-brown, and the remainder of the underside is striped with black and silver markings. During molting, adult pelicans can adopt up to three appearances.

Image Sources: Wikimedia Commons, NOAA

Text Sources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.

Last Updated May 2023