Wing Shape

Using measurements from specimens and known video images, we compared the wing shapes of Pileated Woodpecker, Ivory-billed Woodpecker, and the bird in the Luneau video. 

Pileated: Short, rounded wings

Pileated Woodpecker has relatively short, rounded wings. Aspect ratio (length divided by width in extended wing) varies from 1.4 to 1.9 in our video still-frames of flying birds in Arkansas. Aspect ratio of two specimens in the Cornell Museum of Vertebrates collection are 1.55 and 1.65. Note the red bar in the photo below right is 9.0 cm long.


Pileated Woodpecker in flight, Cache River NWR, Arkansas. Deinterlaced video still.

 

 


Pileated Woodpecker wing, Cornell University Museum of Vertebrates, specimen #49236. The red bar measures 9.0 cm long.

Blurry video frames of Pileated Woodpecker show these broad, rounded wings. In addition to aspect ratio, we can compare the length of the wing to the width of the body. Measurements from video frames and museum specimens show that the extended wing of Pileated Woodpecker varies from 2.5 times to 3.0 times the body width.

                          

Representative single-frame video captures of Pileated Woodpeckers in flight or with extended wings, showing the wide, rounded wing shape. Cache River NWR, Arkansas, 2004-2005.

Ivory-bill: Long, narrow wings

The outstretched right wing of an Ivory-billed Woodpecker in the only known photograph from which the measurements can be taken (below) has an aspect ratio of about 2.4, and its wing-length to body-width radio is about 3.1 to 3.2.

Photo by A.A. Allen and James Tanner, 1935, Singer Tract, Louisiana.

The woodpecker in the Luneau video (below, lower row) is flying almost directly away from us, unfortunately prohibiting measurement of its aspect ratio. However, its wings when fully outstretched both vertically and horizontally appear relatively long compared with those of Pileated Woodpeckers (below, upper row). The wings in these positions consistently measure 3.0 times to 3.2 times the apparent body width. This appearance of long wings relative to body width is more consistent with Ivory-billed Woodpecker than with Pileated.

 

When the Tanner and Allen photograph (above) is subjected to artificial blurring, note that both its wing-tip pattern and its shape resemble a number of frames in the Luneau video.


A photograph (above left) and a film frame (above right) of Ivory-billed  Woodpecker at eye level. Motion blur produces images of the wings that resemble those in the Luneau video in their relatively sleek shape and predominance of white below.

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