Pelicans and Other Fishing Birds: Pelecaniformes
PELICANS AND OTHER FISHING BIRDS: Pelecaniformes
The birds in the Pelecaniformes group are mostly seabirds, and they are some of the most easily recognized birds in the world. All of the birds in the five families have webbing that connects all four toes, although the frigatebirds (FRIGG-it-birdz) have very small webs. The largest birds in the group are the pelicans. The biggest pelicans weigh as much as 33 pounds (15 kilograms). The smallest birds are tropicbirds. Some of them weigh only 10.5 ounces (300 grams).
Many of the birds in this group have interesting bills. Everyone knows the pelicans with their enormous pouches. The Australian pelican has the largest bill of any bird—it is 20 inches (50 centimeters) long. Most of the other birds in the Pelecaniformes group have bills with serrated edges like the blade of a bread knife. These edges help the birds hold slimy fish. Almost all of the bills have a hook on the end. The hooks help tear apart the birds' prey. The anhingas (an-HING-guz) are the only exception. They have sharp, pointy bills that are less than 4 inches (10 centimeters) long.
All of these birds, except for the tropicbirds, have a bare skin pouch or throat sac. The pouches can be fluttered to help cool the birds. The pelicans' fish-catching pouches are the biggest ones. But when male frigatebirds are courting, they can blow up their pouches to look like big red balloons. The birds in this group also have air sacs under the skin that help cushion them when they plunge into the water.
The feathers of the birds in the Pelecaniformes order are not very colorful. Most of them are black, brown, or white. The birds in the cormorant family are unusual because their feathers are not waterproof and can get soaking wet. After swimming, the birds have to spread their wings to dry them in the sun. Although the birds in this group lack bright feathers, other parts of their bodies are surprisingly colorful. The eyes of some pelicans and cormorants are bright green or blue. Many of the birds have yellow, orange, blue, and red throat patches, feet, and bills. Some of the bare parts of the birds turn colorful just during breeding season.
Since most of the birds in the Pelecaniformes order are seabirds, they can be found in oceans, at seashores, and on ocean islands all around the world. A few of the birds live inland near big lakes and rivers. Because they eat only water animals, none of them can live in dry areas. Most of the birds in this group prefer warm waters and avoid the coldest areas. But a few can be found in waters north of the Arctic Circle and in the oceans surrounding Antarctica.
Pelecaniformes depend on fish and other water animals for their food, therefore the habitats they prefer are oceans, seacoasts, rivers, and lakes. Gannets, boobies, tropicbirds, and frigatebirds fish in saltwater, while anhingas are more likely to find their food in freshwater. Some pelicans and cormorants are at home in saltwater, freshwater, and in tidal areas where the two kinds of water mix.
Water animals are the only prey these birds catch, and most of them eat only fish. A few of the birds also eat squid, shrimp and other crustaceans, jellyfish, carrion (mostly dead fish discarded by fishing boats), eggs and chicks of other seabirds, young turtles, and tadpoles.
Although all of the Pelecaniformes birds eat mostly fish, they have several different methods for catching them. Tropicbirds snatch flying fish from the air. Cormorants chase fish at high speeds underwater, propelled by their feet, until they can catch the birds in their beaks. Anhingas chase fish and use their bills as underwater spears to catch them. Gannets plunge into the water from as high as 100 feet (30 meters) to stun and kill their prey. Some pelicans work as teams to drive fish into shallow water where they can easily catch them. And frigatebirds steal fish from other birds.
BEHAVIOR AND REPRODUCTION
Most of these birds feed during the day and spend the night in colonies of several different kinds of birds. Except for the gannets, the birds do not migrate long distances. Pelicans and cormorants move around when food gets scarce, but most of the birds stay in the same area year round. Even though many of them depend on the oceans for food, they usually stay near land.
At breeding time, the males and females show their interest in each other with a variety of courtship displays. Tropicbird pairs swoop and glide together in midair. Pelicans bow to each other and sway in unison. Male frigatebirds blow up their pouches to attract females, and boobies dance with their colorful feet.
When the birds have formed pairs, they crowd together at nesting places. They are more likely to nest in trees and bushes than most seabirds. But pelicans and boobies lay their eggs on the ground, and some tropicbirds nest on cliffs. The nesting areas are crowded because the birds all want to be as close as possible to the feeding areas. When fishing is good, they may only spend thirty minutes a day feeding. However they may spend more time flying from their nests to the fishing spots and back to their nests again.
Since Pelecaniformes usually nest so close together, each bird is constantly warning the birds nearby not to come too close. They wave their wings, poke their beaks at each other and make a lot of noise. Most of the birds can only croak or grunt, but tropicbirds have a shrill scream. The birds usually have plenty of time for arguing, because they spend such a short time feeding every day.
The females lay between one and six eggs. The parents take turns sitting on the eggs until they hatch in twenty-three to fifty-seven days. When the chicks hatch, they are naked and helpless. The parents regurgitate, spit up, food into their own mouths, and the chicks eat from their open bills. The young birds may take as long as four months before they learn to fly.
PELECANIFORMES AND PEOPLE
Pelicans and other birds in this group are the subjects of many legends and stories for children. Many of these birds seem to enjoy the company of humans and follow their fishing ships and even rest on them. Farmers gather the droppings from seabird nesting sites to make fertilizers for crops. In the Far East, cormorants are trained to catch fish for their owners, and some peoples on South Pacific islands still use the long tail feathers of tropicbirds for decorating their clothing.
About one-third of the Pelecaniformes birds are under some kind of threat. Four species are listed as Endangered, facing a very high risk of extinction, or Critically Endangered, facing an extremely high risk of extinction. The problems the birds face include polluted water and loss of habitat for nesting. People have over-fished some parts of the ocean, leaving too few fish for the birds. Some people kill the birds that eat the fish they want for themselves. Some birds have naturally small populations, such as those that live on a few small islands and nowhere else. These birds can be wiped out by animals that are brought to the islands. For example, rabbits brought to some islands eat the plants that the birds need to shade their nests. That means fewer birds are able to raise young.
But there is good news, too. Birds in this group are being helped by people all over the world. In North America, the brown pelican was listed as endangered because of poisonous chemicals, such as dichlorodiphenyltrichloroethane (DDT) that got into their water. When people realized they were harming the birds, the poisons were outlawed. Now the pelicans have made a good comeback and are no longer listed as endangered in some parts of the United States.
WHAT MAKES A GOOD SEABIRD?
Seabirds have many special body parts that help them live on the ocean. Their webbed feet are perfect for swimming. They have air sacs under their skin that make for a soft landing when they plunge into the water. Their long wings help them soar above the waves, and their eyes are good for seeing prey underwater. They have glands that get rid of extra salt, and other glands that supply them with oil to make their feathers waterproof. Seabirds have one more important feature, bills that are designed for grabbing slippery fish.
FOR MORE INFORMATION
del Hoyo, Josep, A. Elliott, and J. Sargatal, eds. Handbook of the Birds of the World. Vol. 1, Ostrich to Ducks. Barcelona: Lynx Edicions, 1992.
Haley, Delphine, ed. Seabirds of Eastern North Pacific and Arctic Waters. Seattle: Pacific Search Press, 1984.
Johnsgard, Paul A. Cormorants, Darters, and Pelicans of the World. Washington, DC and London: Smithsonian Institution, 1993.
Nelson, J. Bryant. The Sulidae: Gannets and Boobies. Oxford, London, Glasgow: Oxford University Press, 1978.
Soper, Tony. Oceans of Seabirds. London: David and Charles Publishers, 1989.
Stuart, Chris and Tilde. Birds of Africa from Seabirds to Seed-Eaters. Cambridge, MA: The MIT Press, 1999.
de Roy, Tui. "To Swim with Pelicans." International Wildlife (January– February 1995): 4–11.
McGrath, Susan. "Shoot-Out at Little Galloo: Angry Fishermen Accuse the Cormorant of Ruining Their Livelihood." Smithsonian (February 2003): 72–78.
Miller, Claire. "Super Scoopers." (pelicans) Ranger Rick (July 1999): 6–12.
Milner, Richard. "Spray It Again." (pelican behavior) Natural History (July 2001): 80–82.
Morgan, S. M., M. A. Ashley-Ross, and D. J. Anderson. "Incubation in Masked Boobies." American Zoologist (December 2000): 1139.
Weimerkirch, Henri, Olivier Chastel, Christophe Barbraud, and Olivier Tostain. "Frigatebirds Ride High on Thermals."Nature (January 23, 2003): 333–334.
The Ocean Conservancy. http://www.oceanconservancy.org (accessed on July 14, 2004).