Brown pelican

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In 1903, President Theodore Roosevelt set aside the first National Wildlife Refuge, Florida's Pelican Island, to protect the Brown pelican from plume hunters.

Appearance

Brown Pelican basks in the sun by Andrea Westmoreland

The brown pelican (Pelecanus occidentalis), also called American brown pelican or common pelican, is the smallest of the six different species of pelicans in the world. They can reach a length of 54 inches long, weigh 8 to 10 pounds, and have a wingspan between 6-1/2 feet and 7-1/2 feet.[1]

They can be identified by their chestnut-and-white necks; white heads with pale yellow crowns; brown-streaked back, rump, and tail; blackish-brown belly; grayish bill and pouch; and black legs and feet.[1]

During the breeding season, the plumage (feathers) turns bright yellow on the head and white on the neck, which both fade to dull yellow and brown during non-breeding.

This bird has a long beak up to 13.5 inches (34.3cm) in length with a hooked tip.[2] As is characteristic of all Pelecanidae family members, the brown pelican has a large throat pouch used for catching prey. Brown pelicans have a dark brown body and white, beige, or pale yellow head. In breeding plumage, the back of the brown pelican’s neck is a bold dark brown. Juvenile brown pelicans typically have brown heads that match body coloration and a white stomach. The short legs and webbed feet of the brown pelican are black in color.

Range

The brown pelican, inhabits the Atlantic, Pacific, and Gulf Coasts of North and South America. On the Atlantic Coast, the species can be found from Nova Scotia to Venezuela and on the Pacific Coast, from British Columbia to south-central Chile and the Galapagos Islands. On the Gulf Coast, the species is found in Florida, Alabama, Louisiana, Texas, Mississippi, and Mexico.[1]

Habitat

Brown pelicans don’t typically occur more than 20 miles (32.3km) offshore.[2] In Florida, brown pelicans are widespread along the coast and can be seen inland during the non-breeding season. Brown pelicans inhabit beaches, sandbars, docks, dredge spoil islands, estuarine islands, mangrove islands, sand spits, and islets.

Behavior

Though they appear awkward on land, Brown pelicans are strong swimmers and masterful fliers. They fly to and from their fishing grounds in V-formations or lines just above the water’s surface. Pelicans fly with their necks folded and their heads resting on their backs, using slow, powerful wing beats. Pelicans are long-lived seabirds. One pelican captured in Florida had been banded 31 years earlier!

Pelicans are primarily fish-eaters, requiring up to four pounds of fish a day. Their diet consists mainly of “rough” fish such as menhaden, herring, sheepshead, pigfish, mullet, grass minnows, topminnows, and silversides. The birds have also been known to eat some crustaceans, usually prawns.

The Brown pelican has a very unique way of foraging, they and the closely related Peruvian Pelican are the only pelican species to perform spectacular head-first dives to trap fish. Unlike other pelicans species who work in flocks to corral their prey, brown pelicans dive headfirst into the water from heights as great as 50 feet (15.2 meters) to scoop up fish near the surface.

Diving steeply into the water, they may submerge completely or only partly—depending on the height of the dive—and come up with a mouthful of fish. Air sacs beneath their skin cushion the impact and help pelicans surface. Once they capture the fish, they tip their head upward or to the side to drain the water from their bill pouch. Pelicans usually forage during the day but may feed at night during a full moon.

Brown pelicans become sexually mature between the age of three and five years old. (Shields 2002) Social and gregarious, brown pelicans breed in large colonies, called rookeries, located in mangrove trees or bushes on estuarine islands.

In most of the nesting range of the brown pelican in the United States—from South Carolina to Florida in the East, in southern California in the West, and in Alabama, Louisiana, and Texas on the Gulf—peak egg-laying usually occurs in March through May.

Breeding begins when the male pelican chooses a nest site. The courtship dance involves the male swaying his head to attract a female mate. When a female chooses him, they will begin to build a nest together, with the female doing most of the construction and the male bringing sticks.

Females lay one to four white eggs, and incubation can take up to 30 days.  Both adults incubate and feed the nestlings, which are blind, featherless, and completely dependent upon their parents. They soon develop down that is soft and silky, followed by feathers.

At least one parent stays with the young at all times for the first month to month-and-a-half. The parents take turns feeding the young, initially by regurgitating small and well-digested fish onto the floor of the nest for the nestlings to eat. As they grow, the nestlings begin feeding on whole fish by reaching their heads into the pouch under the parent’s bill.

The length of time that the young pelicans stay in the nest varies with latitude, but they generally leave the nest within two to three months.[3]

Threats

Brown pelicans have few natural enemies. Although ground nests are sometimes destroyed by hurricanes, flooding, or other natural disasters, the biggest threat to pelicans comes from people.

In the late 19th and early 20th centuries, pelicans were hunted for their feathers, which adorned women’s clothing, particularly hats. Several efforts in the early part of the 20th century were meant to curb the decline of brown pelicans.

During the food shortages following World War I, commercial fishermen claimed pelicans were decimating their industry and slaughtered them by the thousands. The nests were also frequently raided for eggs.

With the advent and widespread use of pesticides such as DDT (dichlorodiphenyltrichloroethane) in the 1940s, pelican populations plummeted due to lack of breeding success. When pelicans ate fish contaminated with DDT, the eggs that they laid had shells so thin that they broke during incubation.

Endrin, once used as a popular insecticide and rodenticide, was another chemical spread to pelicans through the consumption of aquatic organisms. This chemical was highly toxic and directly led to significant pelican mortality. Despite the recovery of the brown pelican, humans still impact their populations in a number of ways. The primary threat that pelicans currently face is pollution. It is estimated that 82,000 birds were killed in the 2010 Deepwater Horizon oil spill, including one out of every 10 brown pelicans in the Gulf of Mexico. https://nationalzoo.si.edu/migratory-birds/species-profile-brown-pelican

Plastic garbage is also a major threat to pelicans and other shorebirds. The toxic chemicals in plastics can be harmful to birds, and birds can be strangled by strips of plastic. Birds also often mistake plastic items for food, and their stomachs can become so filled with plastic items that they die from starvation. A 2015 study found that nine out of every 10 seabirds have plastic in their stomachs. https://nationalzoo.si.edu/migratory-birds/species-profile-brown-pelican

Abandoned fishing line also threatens Brown pelicans along with many other marine animals. It has been estimated that more than 700 adult and immature pelicans die each year in Florida alone from entanglement in recreational fishing gear.[4]

Conservation

Pelican Island was established by President Theodore Roosevelt as the first National Wildlife Refuge in 1903. Pelican Island National Wildlife Refuge, located on Florida’s central east coast, exists today and is a testament not only to the National Wildlife Refuge System but also to the success of protecting our bird species. Click here to learn more about Pelican Island National Wildlife Refuge: http://www.fws.gov/pelicanisland/

While establishment of America’s first National Wildlife Refuge helped reduce hunting pressure on the pelican population, the Migratory Bird Treaty Act of 1918 provided birds with even more protection and worked to end illegal harvests. Click here to learn more about the Migratory Bird Treaty Act

In the mid- and late-1900s, a pesticide called DDT that was used to control mosquitoes had an unintentional effect that almost drove brown pelicans to extinction. DDT caused pelican eggshells to be very thin. This led to low rates of nest success, and populations of pelicans, as well as many other species, were wiped out. By the 1960s, brown pelicans had nearly disappeared along the Gulf Coast and experienced almost complete reproductive failure in southern California. Brown pelicans were almost entirely lost from North America between 1950 and 1970.

In 1970, the U.S. Fish and Wildlife Service listed the brown pelican as endangered, a term that means the species is in danger of extinction throughout all or a significant portion of its range. This status protects the pelican from being directly or indirectly impacted by humans.

In 1972, the Environmental Protection Agency banned the use of DDT in the United States and restricted the use of other pesticides. Since that time, populations of pelicans have recovered and expanded. In 1985, brown pelicans in the eastern United States, including Alabama, all of Florida, Georgia, South Carolina and points northward along the Atlantic Coast, had recovered to the point that the populations were removed from the Endangered Species List.

Brown pelicans responded well to efforts by conservation partners to protect, restore, and manage nesting islands. These actions improved reproductive success in restoring the birds to their historic numbers. As a result of the ban on the use of DDT in the United States, as well as complementary conservation efforts, the species has made a strong comeback and, in view of its improved status, was removed from the list of threatened and endangered species in 2009. The U.S. Fish and Wildlife Service now estimates the global population of brown pelicans at 650,000 individuals. [1]

Documents

Weblinks

References

  1. ↑ 1.0 1.1 1.2 1.3 [https://www.fws.gov/home/feature/2009/pdf/brown_pelicanfactsheet09.pdf FWS Brown Pelican Factsheet
  2. ↑ 2.0 2.1 FWS 10 Thousand Islands Brown Pelican
  3. ↑ National Zoo Brown Pelican Profile
  4. ↑ All About Birds - Brown pelican

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