Friday, March 17, 2006

ENV: More Ivory-bill Putdown

This note to TexBirds from expatriate Rob Fergus:

Today David Sibley and others are publishing their dismissal of the Luneau Ivory-billed Woodpecker video in Science Magazine. Yesterday, Kenn Kaufman posted this on the OH birding email list:

Subject: Woodpecker behavior
Date: Wed, 15 Mar 2006 09:58:51 -0500
The reported rediscovery of Ivory-billed Woodpeckers in Arkansas has been mentioned on ohio-birds many times over the last 11 months, which suggests that this is an acceptable topic for this forum.

Last month in Ecuador we caught up with a related species, the Powerful Woodpecker (Campephilus pollens). I'd missed it on previous trips to South America -- not surprisingly, since it's rather rare. In The Birds of Ecuador, Vol. 1, Robert Ridgely says that it's "rare to uncommon and perhaps local." In Vol. 2, he expands on this to say that its habits are "similar to other Campephilus woodpeckers, though Powerful's home range seems exceptionally large and as a result the species is encountered only infrequently." We found a family group in forest on the east slope. The birds were wary, as one would expect with a large woodpecker, and they were in dense forest, but we were able to follow them at a respectful distance for a long time, and Kim even got decent photos with her small digital camera.

The encounter got me to thinking about our North American species of Campephilus, and I went back and reread Roger Tory Peterson's account of seeing the Ivory-bill in 1942. (This was in RTP's wonderful book, Birds Over America, published in 1948.) He had sought the bird in South Carolina on the basis of rumors there in the 1930s, but finally he went to the Singer Tract in Louisiana, the last place where there were still known to be any living Ivory-bills (two adult females had been seen there a few months earlier). The Singer Tract was big, 80,000 acres, and there were no stakeouts such as roost sites, so Peterson and his companions knew it wouldn't be easy. It wasn't: it took them a whole day and a half to find the birds. Once they found them, though, they were able to follow them for almost an hour.

Now, about these freakishly elusive, supernaturally un-photographable birds in Arkansas... Once you look at the only "proof," the famous four-second video, and realize that it actually shows a Pileated Woodpecker, you have to wonder: What's really going on there?

Kenn Kaufman
Rocky Ridge, Ohio

And this response came from John Arvin:

It is the nature of science to question, and that is a healthy thing. The search effort in Arkansas has no relationship with our project beyond providing the initial spark to do something we have wanted to do for years. I have had an update on our recent activity (see related post) written for a couple of weeks but I have delayed posting it because the scheduling of the volunteer orientation session is still somewhat tentative.

I have not yet seen the Sibley interpretation of the video that purports to show that it could have been of a Pileated Woodpecker so I can't comment on that. As for drawing inferences about IBWO from observations of other Campephilus woodpeckers I would urge extreme caution. I am familiar with all the neotropical species of Campephilus, merged (correctly?) into that genus in the 1980s from Phloeoceastes. None of the Phloeoceastes species sound anything like Campephilus principalis though they all sound basically similar to the rest of Phloeoceastes. The only behavioral trait that I know that they share with Campephilus is the "double-rap" territorial drumming (according to anecdotal accounts from early naturalists; the Cornell expedition of 1935 unfortunately did not get recordings of this sound). Recent mitochondrial DNA analysis shows the two true species of Campephilus (Ivory-billed and Imperial) well separated from extant "Campephilus" (Wm. Moore, 2005), so the degree that one can make assumptions about IBWO from experiences with Powerful, Red-necked, Pale-billed, Crimson-crested, Crimson-bellied, or Magellanic Woodpeckers is questionable.

A range-wide survey for Ivory-billed Woodpecker is about 4 decades overdue. It is one charter member of the Endangered Species List that almost no tax dollars have been spent on until recently, and the vast majority of the funding of the Big Woods Initiative has been from private sources. Considering the amounts of public money that have been spent on the Whooping Crane and California Condor, both species that appear to be incapable of sustaining themselves without being on permanent life support, funding for IBWO has been miniscule.

So, no, we are not pausing due to any challenge to the "Lunneau video". I think Cornell is capable of defending their position on that without our help. There have been schedule set-backs for sure, but these have been in the form of airplane non-availability for specific dates and related logistical tangles, not lack of resolve.

John C. Arvin
Research Coordinator
Gulf Coast Bird Observatory

Jace Stansbury (who i now see has Links, , , , , , ,


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