The Pale-billed Woodpecker is a large, black and white woodpecker with a crested, red head. The bill is heavy and is ivory or yellowish white. It is broadly sympatric (and often syntopic) with the superficially similar Lineated Woodpecker (Dryocopus lineatus); see Similar Species.
The distribution of the Pale-billed Woodpecker broadly overlaps that of the Lineated Woodpecker (Dryocopus lineatus), which is superficially similar to Pale-billed. In all plumages, the Lineated Woodpecker has conspicuous black and white lines along the side of the face. These are lacking in Pale-billed Woodpecker, on which the head is entirely red (male) or is red with a black forecrown (female). The white stripes on the upperparts of the Lineated Woodpecker are roughly parallel with one another, and do not meet, whereas the white stripes on the upperparts of the Pale-billed Woodpecker tend to converge on the lower back (thus forming a “V” pattern) (Ridgely and Gwynne 1989, Stiles and Skutch 1989, Howell and Webb 1995). Additionally, the crest of Lineated Woodpecker is more tufted, in contrast to the somewhat bushier crest of Pale-billed (Howell and Webb 1995). The two species also differ by voice and drum (see Vocalizations and Nonvocal Sounds).
The Pale-billed Woodpecker also is similar to Crimson-crested Woodpecker (Campephilus melanoleucos). Crimson-crested Woodpecker occurs north to western Panama, but is not to overlap with Pale-billed Woodpecker. Crimson-crested Woodpecker has white at the base of the bill and at least some black and white on the sides of the face (Ridgely and Gwynne 1989).
The Pale-billed Woodpecker is sexually dimorphic. The following description is based on Wetmore (1968), and refers to nominate guatemalensis.
Adult male: Entire head (including the throat) is bright red; sometimes there is a small, indistinct grayish brown spot on the auriculars. The feathers on the rear crown and the back of the head are elongated, producing a bushy crest. Neck and back largely black, except for a white or buffy white stripe down each side of the neck to the interscapular area on the back, these two lines turning inward and converging or nearly converging on the lower back. Uppersurface of wings black. Remiges black, except that the outer webs of the outer primaries are dull brown above, and are greenish olive-yellow on the underside; also, the longer primaries are tipped with dull white. Rectrices dull brown; undersurfaces of the outer rectrices are dull olive-brown. Lower foreneck and upper breast black. Remaining underparts are light yellowish buff, narrowly barred with black.
Adult female: Similar to the adult male, but the center of the crown and the forecrown are black, as is the foreneck and throat (except for the chin, which is red).
Hatchling: Nearly naked, with pink skin (Skutch 1969), and a large, conspicuous white knob on either side of the base of the mandible. These knobs apparently persist until the nestling fledges (Skutch 1969).
Immature: Both sexes are similar to the adult female, but the sides of the head are dull black, faintly lined with red. An earlier plumage stage (juvenile?) is similar, but the belly is uniform buffy, lacking the black barring of later plumages. The bill of immature also is darker in color than in adults, although it is not black.
The following color notes refer to adult nominate guatemalensis, and are from Wetmore (1968): Iris light cream-buff. Bill ivory yellow. Tarsi dull greenish gray.
Length: 35.5-38 cm (Howell and Webb 1995)
Wing length (chord) (Short 1982): 172-208 mm
Mass (data from Short 1982): 205-244 g in nominate guatemalensis; 263-282 g in regius