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John Fitzpatrick is coleader of the ivory-billed woodpecker search effort in Arkansas and has been the director of the Cornell Lab of Ornithology and a professor of ecology and evolutionary biology since 1995. Previously, he was executive director of Florida's Archbold Biological Station and curator of birds at Chicago's Field Museum of Natural History. Fitzpatrick is the author of Neotropical Birds: Ecology and Conservation and has been engaged in applying science to real-world conservation issues throughout his career. 
Jerome Jackson is Professor of Biology at Florida Gulf Coast University. His research interests include the behavioral ecology of vertebrate endangered species, niche dynamics of birds, and the history of science in these areas. He has received honors from the American Association for the Advancement of Science, the American Ornithologist's Union, and the Explorer's Club. Jackson cohosted a weekly nature-oriented television segment called "Southern Outdoors" on CBS and currently produces a daily segment called "With the Wild Things" on public radio. |
On January 20, 2006, John Fitzpatrick and Jerome Jackson answered selected viewer questions about the ivory-billed woodpecker. Please note we are no longer accepting questions, but see our links and books section for additional information. Below, read answers to a wide range of questions viewers have e-mailed. Questions for John Fitzpatrick | Questions for Jerome Jackson Q: What about the ivory-billed's eponymous white beak? The NOVA scienceNOW segment didn't discuss it, but it's supposed to be an important field mark and is clearly a distinctive element. Has it been seen in the sightings? Wouldn't seeing it be an important piece of evidence if it was or was not visible in these alleged sightings? A: Unfortunately, none of the people who reported seeing the ivory-billed woodpecker got definitive looks at the bill. All but the first sighting (Gene Sparling's original one, in which he described a bird with a "pale bill") were of a bird in flight. Although those sightings lasted several seconds, and in several cases were through binoculars, the observers were utterly riveted on the wings (because the broad white trailing edge to the wings is the most critical field mark). Casey Taylor, a recently graduated Cornell student who saw an ivory-bill on February 14, 2005, did report that the bird she saw flying overhead (mobbed by two crows) had a long neck and "long straight bill." But even James Tanner, the biologist who studied ivory-bills in the 1930s in Louisiana, wrote that "the bill is not a good field mark." It is difficult to see in flight, it can appear dark against the sky, and the pileated woodpecker's bill can look quite pale. Certainly, anyone who now sees a big woodpecker in the region of study will try to focus on the bill as well as the wings, especially if the bird is perched on a trunk. Q: Regarding the recorded kent-like calls from Arkansas, Russ Charif of Cornell said this: "...several observers from our field teams have reported hearing and seeing blue jays making sounds very much like this in this area." Given that information, isn't it a stretch to say those kent-like calls were "very likely" produced by ivory-bills? A: Thanks for your question, Tom. It's true that we have had several reports from members of our field search crews of blue jays in the White River area making sounds that seemed to them at the time, in the field, to be similar to ivory-bill "kent" notes. During the 2004-2005 search season, only one of those observers was able to get a recording of the sound he heard. When that recording was analyzed, it turned out to be easily recognizable as a blue jay and was not very similar either to the notes in the one known ivory-bill recording (made in 1935), or to the kent-like notes recorded by our autonomous recorders during last year's search (some of which were played during the NOVA scienceNOW program). This year, we have had several more episodes where observers were able to record sounds from blue jays that they thought at the time were very kent-like. In each case, however, the recording was clearly different both from the 1935 ivory-bill recording and from last year's kent-like mystery notes. In fact, even the observers who made the recordings (who are expert birders) agree when they listen to them in the lab that they are different from known ivory-bills and from the mystery notes. Thus, we now have evidence that even experienced observers can be mistaken in their judgments in the field regarding the similarity of two sounds. By all means, we continue to take seriously the possibility that the sounds we've recorded are blue jays. We have consistently made this point clear. However, we also must describe the solid documentary evidence that we do have in hand (in addition to reporting observers'on-the-fly judgments made under difficult field conditions). Our quantitative analyses of the sounds we have recorded shows that they are more similar to ivory-bill sounds than to any known blue jay sounds for which we have recordings. We consider that these kent-like sounds provide suggestive—but not, by themselves, conclusive—evidence of living ivory-bills in this region.—Russ Charif and John Fitzpatrick Q: It's been almost a year since the ivory-billed was allegedly spotted. With all the recent effort looking for it, please explain why there is not more concrete scientific evidence to support its return from extinction. A: This is a very good question. First of all, we did not document a "return from extinction." Rather, we documented the continued presence of at least one bird—a survivor through the intense bottleneck of 20th-century logging. It is not an accident that this species was believed extinct. It is still, obviously, extraordinarily rare, perhaps at this point the world's rarest bird. Indeed, we still lack any substantial evidence that more than one bird exists (although obviously we hope and suspect that a few pairs must still be alive somewhere). Finding a bird as rare as an ivory-billed woodpecker is a tough job for a number of reasons, even with the concerted planning and effort we have been carrying out. (1) We are searching for a bird that as far back as the 1890s was famous for being wary and difficult to locate. (2) The area we are searching includes 550,000 acres of forest, and the bird or birds could be anywhere within it. (3) If the bird that was originally seen was a dispersing, unpaired male, it could be hundreds of miles away by now. Even if it has a permanent home range, it could use 10-20 square miles of this type of forest (ivory-bills may travel 10 to 20 kilometers per day in search of food). (4) In these swamp forests, searchers are limited to going where they can by canoe or must walk slowly and laboriously, sometimes through hip-deep water or thick mud that sucks at their boots and makes every step a struggle. (5) Even if searchers happen to get within range of an ivory-bill, there is no guarantee that they will see it. The trees are dense, making it difficult to see birds even 50 yards away. Ivory-bills are notoriously elusive. Several sightings so far have been glimpses of this magnificent bird as it travels in rapid flight above the treeline, appearing and disappearing so quickly that the viewer is lucky to get binoculars on it, much less a steady shot with a camera. The search team in Arkansas includes outstanding field biologists and woodpecker experts as well as a network of talented volunteers. They're following protocols designed to maximize their chances of finding and documenting the bird, and then are equipped with state-of-the-art technology to aid in the effort. The search team also hopes that birders will search on their own and report their findings, using tips and guidelines posted by the U.S. Fish and Wildlife Service. The groundwork has been laid and the searchers are well prepared. Now they're waiting for their efforts to coincide with a much-needed stroke of luck. Q: With the potential number of ivory-bills being so low, I wonder if there's been any strategy discussed yet for human intervention for their preservation. The number is apparently much fewer than the whooping crane or California condor. If the ivory-billed is back, is the current plan to leave them alone or intervene? A: This is an important point of discussion within the official Recovery Team. Right now there is broad, perhaps unanimous consensus that upon locating one or more breeding pairs, the first steps will be focused on carefully gaining knowledge about the birds in their habitat. We do not anticipate taking any birds into captivity. The key is to "grow back the ancient forest" and let the birds reproduce on their own. The most hopeful feature of this story is that thanks to protection and careful forest management by federal, state, and private agencies, the habitat for ivory-billed woodpeckers is growing better and better all the time in a number of places around the southeastern United States. Q: Has the 2005-2006 winter search in the Big Woods resulted in any new sightings of the ivory-billed woodpecker? I know that much time passed after the initial sightings to release this information to the public, but I wonder if you'd be willing to let us know a little bit about the progress of the search. A: We would love to be able to describe publicly each report we get as it occurs, but working with all our partners in the search process we decided that it could lead to pandemonium and a lot of misinformation if we did so. We'll summarize the results of the current field season publicly in May. For now, suffice it to say that there indeed are some good reasons for our interest and hopes to remain high. Q: Would you as researchers consider the James Audubon method of confirming the species in the wild—shoot one to prove its existence? Probably not, but what about other invasive methods such as mist nets? A: There is still significant research around the world that requires sacrificing a few individuals in order to make voucher specimens for comparative study. However, for a bird species as rare and vulnerable as the ivory-bill, we would never even consider shooting a specimen, for any reason whatsoever. Photographic and video evidence will have to suffice. If there were lookalike species so that we'd need a bird in the hand in order to determine its identity, we might be forced to capture a bird. But the ivory-billed woodpecker is sufficiently distinctive that we are comfortable we can document the bird photographically. Questions for Jerome Jackson Q: We have pileated woodpeckers where I live that look very similar to ivory-billed woodpeckers, but my bird book (Reader's Digest North American Birds) says, "The resemblance is only superficial, for the two species are not closely related." Could you elaborate on this? How close are the two species? A: Thanks for writing, Steffen. Ivory-billed and pileated woodpeckers share many physical characteristics: Both are very large, crested, black-and-white woodpeckers. The pileated is about 18 inches long with a wingspan of about 28 inches, and the ivory-bill is about 20 inches long with a wing-span of about 30 inches. They are close enough in size that at any distance it would be hard to distinguish them based on size. But studies of their DNA and detailed analyses of various aspects of their anatomy clearly tell us that these are not close relatives. The superficial similarities of ivory-billed and pileated woodpeckers constitute a pattern that we refer to as "convergence." With convergence, two or more species may come to look similar as a result of similar environmental pressures. In other cases, there may be an advantage gained by one if it looks like the other, or it could be that they both gain by resembling one another. The pileated woodpecker is in the genus Dryocopus, a group that includes the black woodpecker of Eurasia as well as several other species in Latin America. The ivory-billed woodpecker is in the genus Campephilus , a group with several other species in Latin America, but nowhere else in the world. Interestingly, there are pairs of similar looking Dryocopus and Campephilus woodpeckers in Latin America too, suggesting that one or both are benefiting from this possible mimicry. Why is the pileated so common and found throughout much of North America and the ivory-billed so rare? The pileated seems to have a much broader diet, and it feeds extensively on the ground, thus it needs larger trees primarily for nest and roost cavities. The ivory-bill, on the other hand, is a specialist that seems to prefer the larvae of large beetles that feed on the wood of very large, recently dead trees. Thus, it needs large forests of old trees for both its nest and roost cavities and for its food. There are likely other behavioral differences that play a role in the quite different status of these birds. Q: I have heard that there are ivory-billed woodpeckers in Cuba and on the island of Hispaniola. Could this be true? A: Ivory-billed woodpeckers were once found in old-growth forests of both the southeastern United States and the main island of Cuba. There are no records of them on Hispaniola. As the old-growth forests of both places were cut, the birds disappeared. At the same time, the birds were hunted by the peoples of both areas, and it is clear that the ivory-billed suffered both from hunting and habitat destruction. In 1986, ivory-bills were sighted by Cuban, American, and Kenyan ornithologists in the mountains of eastern Cuba (where they had been known in the 1950s). The ivory-bill's closest living relative is the imperial woodpecker from the mountains of western Mexico, and its other relatives all live in Latin America. We do not know if ivory-bills got to North America by way of Mexico and along our Gulf coast to Florida and then to Cuba, or by way of Yucatan to Cuba and then to Florida. The Cuban ivory-bill is considered the same species as the North American ivory-bill, but it is very slightly smaller. Both the Cuban and the North American ivory-bill are either extremely rare or extinct. Q: References to the ivory-billed from the early 1900s don't indicate that the species was all that secretive or elusive. Now most searchers are suggesting that the bird is very secretive and elusive, which is part of the reason they claim it's hard to find. Can you explain this discrepancy in the way the bird is characterized? Is the ivory-billed any more secretive than a pileated? A: Steve, perhaps the best answer to your question is by saying that we don't know. The writings of early naturalists in North America suggest that the ivory-billed was locally common, although never as numerous as the pileated woodpecker. It is likely that there are some times of the year that it would be more likely to be seen, such as winter when there are no leaves on the trees, or during nesting when the birds could be depended on to repeatedly return to the same area (the nest site). The ivory-bill has a very large home range, perhaps traveling over several square miles in the course of a day. Thus, getting to see one would depend on the viewer being in the right place at the right time. That aspect of the ivory-billed woodpecker would make it difficult to find, but would not necessarily mean that it was deliberately eluding observers. The very large home range, coupled with very small numbers of ivory-bills and their very inhospitable habitat, might work together to make them seem elusive. On the other hand, your suggestion that references do not indicate that the species was all that secretive or elusive is not quite correct. Many references do agree with this supposition, but there are some that do suggest they were elusive. For example, the ornithologist Robert Ridgway, who found ivory-bills in south Florida in 1898, commented on the differences between the pileated and the ivory-bill, noting "The ivory-bill...is comparatively quiet and secluded...." Without having an observable population of ivory-bills, we can only guess as to whether they are being elusive or not. The writings of those who actually knew ivory-bills vary greatly in the opinions expressed regarding their secretiveness and observability. Q: Do you believe it's impossible for the ivory-billed to still be in existence, or do you just believe that the evidence of its existence so far is not conclusive? A: For many years, I have championed the idea that ivory-billed woodpeckers could still be with us. There have been continuing reports from many observers over the years, and I believe and hope that some of them might be valid. Arguing for the possible existence of the ivory-bills is the steady improvement in their potential bottomland hardwood forest habitats since the 1940s. We have hope today because of the protection of many of these forests such as White River National Wildlife Refuge (established in 1935) and the protection of other forested areas by hunt clubs, state lands, and other federal properties. I do, however, believe that the evidence presented thus far from Arkansas is inconclusive. The rigors of science require independent evaluation and confirmation of data by other scientists. Thus far what has been presented is a good hypothesis, but not confirmation. None of us can know for certain what another person saw, and the physical pieces of evidence provided thus far, a four-second video and recordings thought to be of ivory-bill double raps and vocalizations, all have some alternative possibilities. I have spent time in the Bayou DeView/Cache River/White River forests, and I do believe there is some potential for ivory-bills to be there. It is also possible that they are not. We've just got to get solid documentation. Q: Dr. Jackson, In addition to the video clip, are you skeptical of the sightings a number of experienced birders and ornithologists have reported of the ivory-billed in Arkansas? Their evidence was strong enough to be published in the peer-reviewed journal Science. Will you also publish your rationale to the contrary? A: Thanks for your question, Allison. It is a tough one to answer because it hits at the very foundations of science. Yes, those several sightings were included in the Science article, but a sighting does not constitute scientific confirmation. Other scientists must be able to verify that the evidence is what it is reported to be, and there is no way that anyone can know what these people saw. It might have been an ivory-billed woodpecker, but it might not have been. I don't believe the sightings alone would have been considered publishable in Science or in any major scientific journal. I also do not believe that the other evidence that was presented was strong enough to justify publication in Science. Many maybes do not constitute confirmation for me. If I were to sit down with each of these observers and listen to the details of each observation, I might well be convinced by one or more of them. But my being convinced that they "probably" saw an ivory-bill does not constitute scientific proof. What it would mean is that I had faith that they truly believed they had seen one and that I also believed they had seen one. I might personally accept the observation on faith but could not accept it as scientific evidence because there is no physical evidence that I or anyone else could independently examine and know for certain that the bird was an ivory-bill. These observations provide hope that the ivory-bill may still live and that additional documentation may be found. |
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