Not to be confused with: Ivory-billed Woodcreeper
| Ivory-billed Woodpecker | |
|---|---|
 A hand-coloured photo of a male from 1935 | |
| Information | |
| Range | southeastern United States |
| Scientific Classification | |
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Aves |
| Order | Piciformes |
| Family | Picidae |
| Genus | Campephilus |
| Species | Campephilus principalis |
| Conservation Status | |
 Critically Endangered | |
The Ivory-billed woodpecker (Campephilus principalis), is or was one of the largest woodpeckers in the world, at roughly 20 inches in length and 30 inches in wingspan. It was native to the virgin forests of the southeastern United States (along with a separate subspecies native to Cuba). Due to habitat destruction, and to a lesser extent hunting, its numbers have dwindled to the point where it is uncertain whether any remain, though there have been reports that it has been seen again. Almost no forests today can maintain an ivory-billed woodpecker population.
The species is listed as critically endangered and possibly extinct by the International Union for Conservation of Nature (IUCN). The American Birding Association (ABA) lists the ivory-billed woodpecker as a Class 6 species, a category the ABA defines as "definitely or probably extinct."
Reports of at least one male ivory-billed woodpecker in Arkansas in 2004 were investigated and subsequently published in April 2005 by a team led by the Cornell Lab of Ornithology. No definitive confirmation of those reports emerged, despite intensive searching over five years following the initial sightings.
A $10,000 reward was offered in June 2006 for information leading to the discovery of an ivory-billed woodpecker nest, roost or feeding site. In December 2008, the Nature Conservancy announced a reward of $50,000 to the person who can lead a project biologist to a living ivory-billed woodpecker.
In late September 2006, a team of ornithologists from Auburn University and the University of Windsor published reports of their own sightings of ivory-billed woodpeckers along the Choctawhatchee River in northwest Florida, beginning in 2005. These reports were accompanied by evidence that the authors themselves considered suggestive for the existence of ivory-billed woodpeckers. Searches in this area of Florida through 2009 failed to produce definitive confirmation.
Despite these high-profile reports from Arkansas and Florida and sporadic reports elsewhere in the historic range of the species since the 1940s, there is no conclusive evidence for the continued existence of the ivory-billed woodpecker; i.e., there are no unambiguous photographs, videos, specimens or DNA samples from feathers or feces of the ivory-billed. Land acquisition and habitat restoration efforts have been initiated in certain areas where there is a relatively high probability that the species may have survived to protect any possible surviving individuals.
Taxonomy[]
A comparison of the ivory-billed woodpecker (bottom) with the pileated woodpecker (top)
The Ivory-billed is the type species for the genus Campephilus, a group of large American woodpeckers. Although the Ivory-billed looks very similar to the pileated woodpeckers (Dryocopus pileatus) they are not close relatives as the latter is a member of the genus Dryocopus.
Ornithologists have traditionally recognized two subspecies of this bird: the American Ivory-billed, the more famous of the two, and the Cuban ivory-billed woodpecker. The two look similar despite differences in size and plumage. There is some controversy over whether the Cuban ivory-billed woodpecker is more appropriately recognized as a separate species. A recent study compared DNA samples taken from specimens of both ivory-billed birds along with the imperial woodpecker (Campephilus imperialis), a larger but otherwise very similar bird. It concluded not only that the Cuban and American Ivory-billed woodpeckers are genetically distinct, but also that they and the imperial form a North American clade within Campephilus that appeared in the Mid-Pleistocene. The study does not attempt to define a lineage linking the three birds, though it does imply that the Cuban bird is more closely related to the imperial.
The American Ornithologists' Union Committee on Classification and Nomenclature has said it is not yet ready to list the American and Cuban as separate species. Lovette, a member of the committee, said that more testing is needed to support that change, but concluded that "These results will likely initiate an interesting debate on how we should classify these birds." Before this study, it was thought that the Cuban Ivory-billed were descended from mainland woodpeckers, either introduced to Cuba by Native Americans or accidentals that flew to the island themselves.
While recent evidence suggesting that American ivory-billed woodpeckers may still exist in the wild has caused excitement in the Ornithology community, no similar evidence exists for the Cuban Ivory-billed bird, believed to be extinct since the last sighting in the late 1980s.
Description[]
The contrast in plumage of the male (above) and female (below)
The ivory-billed woodpecker ranks among the largest woodpeckers in the world and is the largest in the United States. The closely related and likewise possibly extinct imperial woodpecker of western Mexico is, or was, the largest woodpecker. The Ivory-billed has a total length of 48 to 53 cm (19 to 21 in) and, based on very scant information, weighs about 450 to 570 g (0.99 to 1.26 lb). It has a typical 76 cm (30 in) wingspan. Standard measurements attained included a wing chord length of 23.5–26.5 cm (9.3–10.4 in), a tail length of 14–17 cm (5.5–6.7 in), a bill length of 5.8–7.3 cm (2.3–2.9 in) and a tarsus length of 4–4.6 cm (1.6–1.8 in).
The bird is shiny blue-black with white markings on its neck and back and extensive white on the trailing edge of both the upper- and underwing. The underwing is also white along its forward edge, resulting in a black line running along the middle of the underwing, expanding to more extensive black at the wingtip. In adults, the bill is ivory in color, chalky white in juveniles. Ivory-bills have a prominent crest, although in juveniles it is ragged. The crest is black in juveniles and females. In males, the crest is black along its forward edge, changing abruptly to red on the side and rear. The chin of an ivory-bill is black. When perched with the wings folded, ivory-bills of both sexes present a large patch of white on the lower back, roughly triangular in shape. These characteristics distinguish it from the smaller and darker-billed pileated woodpecker. The pileated normally is brownish-black, smoky, or slaty black in color. It also has a white neck stripe but the back is normally black. Pileated juveniles and adults have a red crest and a white chin. Pileateds normally have no white on the trailing edges of their wings and when perched normally show only a small patch of white on each side of the body near the edge of the wing. However, pileated woodpeckers, apparently aberrant individuals, have been reported with white trailing edges on the wings, forming a white triangular patch on the lower back when perched. Like all woodpeckers, the ivory-bill has a strong and straight bill and a long, mobile, hard-tipped, barbed tongue. Among North American woodpeckers, the ivory-bill is unique in having a bill whose tip is quite flattened laterally, shaped much like a beveled wood chisel.
The bird's drum is a single or double rap. Four fairly distinct calls are reported in the literature and two were recorded in the 1930s. The most common, a kent or hant, sounds like a toy trumpet often repeated in series. When the bird is disturbed, the pitch of the kent note rises, it is repeated more frequently, and is often doubled. A conversational call, also recorded, is given between individuals at the nest, and has been described as kent-kent-kent. A recording of the bird, made by Arthur A. Allen, can be found here.
The ivory-billed woodpecker is sometimes referred to as the Grail Bird, the Lord God Bird, or the Good God Bird, all based on the exclamations of awed onlookers. Other nicknames for the bird are King of the Woodpeckers and Elvis in Feathers.
Status[]
Heavy logging activity exacerbated by hunting by collectors devastated the population of ivory-billed woodpeckers in the late 19th century. It was generally considered extinct in the 1920s when a pair turned up in Florida, only to be shot for specimens.
In 1932, a Louisiana state representative, Mason Spencer of Tallulah, disproved premature reports of the demise of the species when, armed with a gun and a hunting permit, he killed an ivory-billed woodpecker along the Tensas River and took the specimen to his state wildlife office in Baton Rouge.
By 1938, an estimated twenty woodpeckers remained in the wild, some six to eight of which were in the old-growth forest called the Singer Tract, owned by the Singer Sewing Company in Madison Parish in northeastern Louisiana, where logging rights were held by the Chicago Mill and Lumber Company. The company brushed aside pleas from four Southern governors and the National Audubon Society that the tract be publicly purchased and set aside as a reserve. By 1944, the last known ivory-billed woodpecker, a female, was gone from the cut-over tract.
Reported Sightings: 1940s to 1990s[]
The Cuban subspecies, Campephilus principalis bairdii
The only footage of the ivory-billed woodpecker was recorded in 1935 along with the sound of its call. The ivory-billed woodpecker was listed as an endangered species on March 11 1967, though the only evidence of its existence at the time was a possible recording of its call made in East Texas. The last reported sighting of the Cuban subspecies (Campephilus principalis bairdii), after a long interval, was in 1987; it has not been seen since. The Cuban Exile journalist and author John O'Donnell-Rosales, who was born in the area of Cuba with the last confirmed sightings, reported sightings near the Alabama coastal delta in 1994, but these were never properly investigated by state wildlife officials.
Two tantalizing photos were given to Louisiana State University museum director George Lowery in 1971 by a source who wished to remain anonymous but who came forward in 2005 as outdoorsman Fielding Lewis.
The photos, taken with a cheap Instamatic camera, show what appears to be a male Ivory-billed perched on the trunks of two trees in the Atchafalaya Basin of Louisiana. The bird's distinctive bill is not visible in either photo and the photos – taken from a distance – are very grainy. Lowery presented the photos at the 1971 annual meeting of the American Ornithologists Union. Skeptics dismissed the photos as frauds; seeing that the bird is in roughly the same position in both photos, they suggested they may have been of a mounted specimen.
There were numerous unconfirmed reports of the bird, but many ornithologists believed the species had been wiped out completely, and it was assessed as "extinct" by the International Union for Conservation of Nature and Natural Resources in 1994. This assessment was later altered to "critically endangered" on the grounds that the species could still be extant.
2002 Pearl River Expedition[]
In 1999, there was an unconfirmed sighting of a pair of birds in the Pearl River region of southeast Louisiana by a forestry student, David Kulivan, which some experts considered very compelling. In a 2002 expedition in the forests, swamps, and bayous of the Pearl River Wildlife Management Area by LSU, biologists spent 30 days searching for the bird.
In the afternoon of 27 January 2002, after ten days, a rapping sound similar to the "double knock" made by the ivory-billed woodpecker was heard and recorded. The exact source of the sound was not found because of the swampy terrain, but signs of active woodpeckers were found (i.e., scaled bark and large tree cavities). The expedition was inconclusive, however, as it was determined that the recorded sounds were likely gunshot echoes rather than the distinctive double rap of the ivory-billed woodpecker.