Woodpecker video is challenged and defended.

The most famous bird video in the United States--a blurry 4 seconds released last year as evidence that the ivory-billed woodpecker still exists--probably just shows a common pileated woodpecker, argues a team including David Sibley, author of the popular Sibley bird guides.

Oh no, it doesn't, says the Cornell University team that originally identified the bird. John Fitzpatrick and his colleagues stand by their interpretation that the video caught an ivory-billed woodpecker flapping off into the woods.

Both groups present their case in the March 17 Science. That's the journal that in April 2005 rocked the birding world by publishing the Cornell group's contention that at least one of the big, showy birds survives in flooded lowlands of Arkansas' Big Woods (SN: 5/7/05, p. 291). The search team has built its case on fleeting sightings by experienced bird-watchers, sound recordings, and the video.

Now, Sibley and his colleagues present alternative interpretations of the images. For example, the Cornell team interprets a white smear beside a tree trunk as the distinctive topside wing patch on a partially hidden, perching ivory-billed.

Sibley, however, proposes that it could be the underside of a wing of a pileated woodpecker launching itself away from the tree. If the bird is flying instead of perching, Sibley argues, the Cornell group's calculations of bird size no longer work. Fitzpatrick counters that a flying pileated woodpecker would show more black than is visible in the video.

Such debate makes for healthy science, says woodpecker researcher Jeffrey Walters of Virginia Polytechnic Institute and State University in Blacksburg. However, the only way to settle the debate is to find more evidence out in the woods.--S.M.