Shoebill: Balaenicipitidae

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SHOEBILL: Balaenicipitidae

PHYSICAL CHARACTERISTICS

Shoebills are large, gray wading birds, birds that search for food in shallow water, that stand about 4.5 feet (1.4 meters) tall. They are named for their enormous bills that look like wooden shoes. Some people call them whale-heads because their heads are shaped like the body of a blue whale. In any case, their huge hooked bills make them easy to recognize. Although shoebills have similarities to herons and storks, they are in a family all by themselves. Scientific tests show that they may be more closely related to pelicans than storks and herons.

Shoebills have gray patches on their yellowish bills. Some people can tell individual shoebills apart by the bill markings. Shoebills' legs and toes are long, and they have unusually large, front-facing eyes with yellow irises. On the back of their heads, they have a small crest that rises when they are frightened or excited. shoebills are about 4 feet (1.2 meters) in length from the tip of their bills to the end of their tails, and their wingspan is 8.5 feet (2.6 meters). Their bills are 7.5 inches (19.1 centimeters) in length and their toes are between 6.6 and 7.3 inches
(16.8 and 18.5 centimeters) long. Male shoebills are a little larger than the females.

GEOGRAPHIC RANGE

Shoebills live in central Africa. Most of them are in southern Sudan and northern Uganda. Some are also found in Tanzania, Democratic Republic of Congo, Central African Republic, and Rwanda.

HABITAT

Shoebills live in swamps or beside marshy lakes or rivers where floating ferns, cattails and papyrus (puh-PIE-rus) grow. Papyrus is a tall water plant that covers some swampy areas.

DIET

Shoebills are carnivores, meat eaters, which eat mostly fish. They spread out over the water and keep to themselves when they are fishing. Shoebills have three different ways of fishing. They often stand in the water, waiting for prey to swim by. They can stand almost motionless with their bills pointing downward for a half hour or longer. Sometimes they stand on floating plants and watch for prey. Their long toes spread their weight on the plants, but after a while, the birds gradually sink into the water. If there is an open channel of slow-moving water, shoebills might walk slowly along it. Channels are trails that big mammals make through the thick water plants, opening up places where shoebills would not be able to go otherwise.

The best place for shoebills to fish is a marsh or pond where the water is drying up. Then large numbers of fish have to swim close together and they are easy to catch. Shoebills eat mostly lungfish and other fish that swim near the surface. But they also catch turtles, water snakes, lizards, frogs, young crocodiles, young water birds, snails, and rodents. They catch fish that are as long as 19 inches (48 centimeters). They prey catch by sight and possibly by hearing, but shoebills are not able to feel the underwater animals with their bills.

A WILD WAY TO STAY COOL

When people have wet skin, they usually feel cooler than when it is dry. Storks, New World vultures, and possibly shoebills have discovered the same thing. They often squirt their liquid droppings onto their legs to cool off. As the liquid evaporates, the blood in their legs is cooled. Then the cool blood circulates to the rest of the bird's body. Scientists have studied the birds' body temperatures when their legs are wet and when they are dry, and they have found that the birds are cooler when their legs are wet.

When shoebills are fishing, they stand and point their bills straight down so that they can see with both eyes. If they spot a fish or other water animal, they instantly throw their wings forward and their heads downward. Then they quickly snap up the prey with their bills. The hook on their bills helps to hold slippery prey. After swallowing prey, shoebills usually drink some water.

BEHAVIOR AND REPRODUCTION

Shoebills usually fly low and not very far, but they can also spread their broad wings and soar high on warm air currents. If a shoebill is frightened while feeding, it flies straight up and flaps slowly and silently away, with its head tucked back onto its breast. But it soon lands again and continues to stand or move along silently.

The shoebills living in each part of Africa have learned when it is best for them to breed. In some areas, the birds wait until the beginning of the dry season, when water levels are getting low and fish are easy to catch. Other areas have two rainy seasons, so the birds have to start breeding while it is raining. Then when the young birds need the most fish, the dry season will be starting.

Each pair of shoebills nests by itself, and they defend a wide territory around the nest. The only time they are noisy is during courtship displays, where they bow to each other, clatter their bills, and squeal or whine. The male and female both help to build the nest out of water plants. They start by building a floating platform that is up to 10 feet (3 meters) across. On top of this platform, they build a nest that is about 4.5 feet
(1.4 meters) across. In some places, nests are built on termite mounds that stick out of the water. The birds work the plant stems into the nest by jumping up and down on them and poking them in with their long toes.

Females lay between one and three dull white eggs. The parents take turns sitting on the eggs. On very hot days, they swallow cool water and regurgitate (re-GER-jih-tate) it, spit it up, on the eggs to keep them cool. When the chicks hatch, the parents care for them by shading them from the sun, cooling them with regurgitated water, protecting them from predators, and catching food for them. When a parent arrives at the nest, the downy chicks beg to be fed by making a little noise and pecking at the adult's legs or bill. The adult then regurgitates some food, and the young birds eat out of the parent's bill.

The young stay in the nest for as long as 105 days. During the first thirty-five days, they cannot stand, and one adult stays with them at all times. After that, both parents leave to hunt for food for the growing chicks. By ninety-five days, the young birds wander off the nest, and they can fly about ten days later.

SHOEBILLS AND PEOPLE

Shoebills appear in wall paintings and hieroglyphics (high-ruh-GLIH-fix), symbol writing, used in ancient Egypt. People told scary stories about shoebills, and the birds were protected because people were afraid to kill them. There is even a myth that people who are fishing will have bad luck if they see a shoebill or mention its name.

Some African countries honor shoebills by putting their pictures on postage stamps. However people also cause problems for shoebills. Farmers raising rice and other crops destroy their habitat, wetlands are drained so people can build on them, and their nesting swamps are sometimes burned to make it easier for people to fish and hunt there. Some people catch the birds and sell them to zoos, and others hunt them for food.

CONSERVATION STATUS

The shoebill is listed as Near Threatened, which means it could become endangered in the near future. The birds are so secretive that scientists have a hard time counting them, but there may be fewer than 15,000 shoebills left in the wild. Although laws protect the shoebill, it is still threatened by people who break the laws. Many local people are working to help the wildlife. By protecting the wild animals, including shoebills, tourists are encouraged to visit their area in order to see the animals. Tourists bring money by staying in hotels, eating at restaurants, buying souvenirs, and signing up for boat tours where they can see animals in the wild.

FOR MORE INFORMATION

Books:

Brown, L. H., Emil K. Urban, and K. Newman. The Birds of Africa. Vol. 1, Ostrich to Falcons. London: Academic Press, 1982.

Capper, David R., Guy C. L. Dutson, and A. J. Stattersfield, eds. Threatened Birds of the World. Barcelona: Lynx Edicions; and Cambridge: BirdLife International, 2000.

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.

Hancock, James A., James A. Kushlan, and M. Philip Kahl. Storks, Ibises and Spoonbills of the World. London, San Diego, New York: Academic Press Limited, 1992.

Stuart, Chris and Tilde. Birds of Africa, From Seabirds to Seed-Eaters. Cambridge, MA: The MIT Press, 1999.

"Shoebill Stork." International Wildlife Encyclopedia, 3rd ed. Vol. 17. Tarrytown, NY: Marshall Cavendish Corporation, 2002.