Ivory-billed Woodpecker


Description and biology

The ivory–billed woodpecker is the largest North American woodpecker. It measures from 18 to 20 inches (46 to 51 centimeters) long. The color of the plumage (covering of feathers) on its body is a shiny blue–black.

Broad white markings appear on its wings and neck. Its strong, straight, heavy bill is pure white. Males of the species have a bright red crest (projecting tuft on top of its head); females have a black one. The bird has short legs and feet that end in large, curved claws.

The ivory–billed woodpecker uses its bill to strip bark from dead or dying trees in search of wood–boring beetle larvae and other insects. Male–female pairs occupy a large territory of up to 4,000 acres (1,600 hectares).

Breeding season lasts from March to June. The woodpecker creates a nest by boring out a hole high up in a tree. The female ivory–billed woodpecker then lays a clutch (eggs produced at one time) of 3 to 5 glossy white eggs in the unlined hole.

Both parents incubate (sit on or brood) the eggs for about 20 days. The nestlings fledge (develop flying feathers) about 35 days after hatching.

Habitat and current distribution

Many biologists (people who study living organisms) consider the ivory–billed woodpecker to be extinct, or almost extinct. Up until the early 1990s, they believed that a few of the woodpeckers still survived in eastern Cuba.

There had been unconfirmed sightings of the bird along the Gulf Coast of North America from the 1950s through the 1970s. These “sightings” led biologists to believe at the time that the bird might still survive in remote forests in Louisiana, South Carolina, Mississippi, Georgia, or Florida.

In the 1990s, biologists had lost hope that the bird existed anywhere, but in April 1999, a student saw what many believe was a couple of ivory–billed woodpeckers on the Pearl River in Louisiana. There were other credible, but unconfirmed, sightings after that.

In the United States, the woodpecker inhabits hardwood swamp forests and, on occasion, pine forests. In Cuba, it occupies mixed pine and hardwood forests.

History and conservation measures

The ivory–billed woodpecker was always considered rare throughout its range in the United States. At the end of the nineteenth century, the logging and clearing of virgin swamp forests in the southern United States decimated the remaining population of these woodpeckers. Hunters and trappers also quickened the bird’s decline. By 1941, the ivory–billed woodpecker population was estimated at 24 birds in five scattered areas.

Just seven years later, the last identified population disappeared. Over the next 30 years, reports were made that the bird had been sighted. However, none of these were ever confirmed. No reports had been made in the 20 years leading up to 1999.

In Cuba, the ivory–billed woodpecker was thought to have existed over much of the island. By 1956, due to the clearing of its natural habitat, the bird’s Cuban population numbered only about 12. These birds disappeared shortly afterward, and the woodpecker was believed to have become extinct on the island.

In 1986, however, Cuban biologists working in eastern Cuba found three woodpeckers in a hilly pine forest called Ojito de Agua. Hopes were raised that the birds could make a comeback, but expeditions to find these birds in 1991 and 1993 proved futile.

In 1996, the ivory–billed woodpecker was declared extinct by the International Union for the Conservation of Nature and Natural Resources (IUCN). In 1999, with several new sightings of the bird in southeastern Louisiana, a flurry of research and then extensive searches were conducted in the Pearl River area in 2000 and 2001.

In 2002, Cornell University’s Lab of Ornithology (study of birds) in cooperation with Zeiss Sports Optics and the Louisiana Department of Wildlife and Fisheries used high–tech recording equipment to record the sounds at twelve different positions within the remote forest area for a period of three months.

The project turned up no indication of the ivory–billed woodpecker’s presence. The IUCN changed the bird’s status to critically endangered, in the hope that there are a few remaining birds in the wild.

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