On the back of the head is a small tuft of feathers that can erect in a crest. Adult breeding plumage does not differ from non-breeding plumage. The underparts are a lighter shade of grey. The primaries are black-tipped and secondaries have a greenish tint. The plumage is slaty blue-grey overall with a darker grey head. Males are larger than females and have longer bills. ![]() Large, somewhat frightful looking birds, shoebill storks stand 110 to 140 cm tall. Primary Diet: carnivore (Eats terrestrial vertebrates, Piscivore ) Before swallowing, the prey is usually decapitated.Īnimal Foods: amphibians reptiles fish carrion mollusks In order to expel the vegetation, shoebill storks sway their heads from side to side while keeping hold of the prey. Along with the prey, a mouthful of vegetation is also collected. It must regain its balance and start from the standing position again. After a collapse, a shoebill stork cannot immediately perform a second collapse. The head and neck quickly stretch forward into the water causing the bird to over-balance and collapse forwards and downwards. The two mechanisms by which shoebill storks hunt are "stand and wait" and "wade and walk slowly." When a prey item is spotted, shoebill storks will begin the "collapse". ![]() If the water is deep, a firm, floating platform of vegetation must be present in order to hunt. The most suitable area for catching prey is one with shallow water and tall vegetation to camouflage the bird as it stalks prey. On occasion, they will also consume frogs, monitor lizards, turtles, young crocodiles, mollusks and carrion. The main part of their carnivorous diet consists of lungfish ( Protopterus), bichirs ( Polypterus), catfish, tilapia ( Tilapia) and watersnakes. Shoebill storks spend most of their time foraging in aquatic environments. IUCN Red List of Threatened Species: vulnerable If they do breed, the young imprint on the zookeepers and will not go on to breed themselves when they reach adulthood. There have been few accounts of shoebill storks breeding in captivity. This encourages native people to capture and sell these birds to zoos, thus reducing wild populations. They sell for US $10,000-$20,000 making them the most expensive birds in the zoo trade. The demand for shoebill storks in zoos is very high. Another cause for concern is the zoo trade. Fishermen disturb the shoebill's habitat, especially their feeding areas. They have specific habitat needs for nesting and foraging and their swamps and marshes are being rapidly converted to agricultural land and cattle grazing. ![]() Shoebill storks are most threatened by habitat destruction. ![]() Local folklore also protects shoebill storks and native people are taught to respect and even fear these birds. They are protected by law in Sudan, the Central African Republic, Uganda, Rwanda, Zaire and Zambia, and included in Class A of the African Convention of Nature and Natural Resources. They are also listed in Appendix II of CITES. The IUCN rates shoebill storks as "Lower risk - near threatened". Since populations of shoebill storks are scattered and most are inaccessible to humans (or nearly so) for much of the year, it is hard to get a reliable number. There have been many estimates of shoebill stork populations, but the most accurate is 11,000-15,000 birds over the entire range.
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