Northern Bald Ibis


Description and biology

The northern bald ibis, also known as the waldrapp, grows to an average length of 27.5 to 31.5 inches (70 to 80 centimeters). The birds’ naked red head and fringe of dark feathers around its neck give it the appearance of a vulture. Its feathers, chiefly black in color, have an iridescent bronzegreen gloss.

A patch on its forewing or "shoulder" is a shade of shiny bronze–purple. The bald ibis has a long tapering bill that curves downward. It uses its bill to probe for and feed on insects, such as beetles and grasshoppers, and fish and other aquatic animals.

The northern bald ibis nests in small colonies, usually on rocky cliffs or ledges in semi–arid (partly or mostly dry) areas near water. Breeding season begins in February.

In late March or early April, after making a nest of straw, grasses, and twigs, a female northern bald ibis lays a clutch (eggs produced at one time) of 3 to 4 eggs. In about 60 days, the nestlings will have hatched and fledged (developed flying feathers). By the end of June, they will leave the nesting grounds with their parents.

Main predators of the bald ibis include ravens (which sometimes prey on nestlings or eggs) and falcons (which have been seen attacking nesting ibises).

Habitat and current distribution

Although the range of the northern bald ibis seems to have increased in recent years, the bird is considered critically endangered. The majority of birds inhabit northwest Africa, mainly Morocco.

Although the bird was thought to be extinct in the Middle East, in the spring of 2002 a colony of the species was found in central Syria, consisting of three male–female pairs that were at the time incubating eggs and a seventh individual. Biologists (people who study living organisms) believe the bird’s total population now numbers around 315.

The northern bald ibis prefers to inhabit rocky, semi–arid regions, often with running water nearby. Feeding habitat includes sea coasts, edges of streams, river beds, sand banks, marshes, and other damp ground with sparse vegetation.

History and conservation measures

The northern bald ibis once ranged throughout southern Europe, the Middle East, and northern Africa, including the coast along the Red Sea. At the end of the seventeenth century, the bald ibis could still be found in European countries such as Austria, Italy, Germany, Switzerland, Hungary, and portions of the Balkan Peninsula.

Over a period of several centuries, the northern bald ibis slowly disappeared from its historic range. Widespread hunting and capture, both for food and zoo collections, contributed to the bird’s decline. In the twentieth century, the use of pesticides on farmland, especially in Turkey, poisoned many bald ibises.

With the population already very low, it was disastrous to the species when, in May 1996, a total of 21 adults were found dead and another 17 disappeared from their Moroccan colonies. The exact cause of this major loss is still not known.

Conservation programs on behalf of the bald ibis have begun in Morocco. Massa National Park, a 40–mile (64–kilometer) belt along the Atlantic coast between the cities of Agadir and Tiznet, was recently established.

This wetland site is home to almost half of the breeding ibis population remaining in Morocco. It is also a major wintering area. The number of northern bald ibises has increased from a low of 220 birds in the mid–1990s to about 315 in the early 2000s.

This bird breeds well in captivity. Stocks of captive northern bald ibises are maintained in Birecik, Turkey, and at Tel Aviv University in Israel. Biologists hope to reintroduce these captive–bred bald ibises to undisturbed areas in their former range.

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