Post by hi224 on May 3, 2021 5:06:26 GMT
American ivory-billed woodpecker was a species of woodpecker that lived in the Southern United States. The last verifiable sightings of an ivory-billed took place in 1944. Unfortunately, as a result of deforestation destroying the birds' habitat, they went extinct at around that time.
There have been persistent rumours, discussed on this subreddit, that perhaps the ivory-billed woodpecker still exists in America. In 2004, an alleged sighting in Arkansas sparked significant academic interest in the continued existence of the bird. Researchers from the Cornell Laboratory of Ornithology, led by John Fitzpatrick, investigated the woods where the bird was allegedly spotted, producing recordings of possible ivory-billed calls and knocks, and a four-second video that they claimed captured an ivory-billed woodpecker. Following this, the researchers publicly announced that the ivory-billed continued to exist, sparking academic debate, and many searches for the bird. In this post, I will explain why the ivory-billed woodpecker is in fact extinct, and why it matters.
Ivory-Billeds in the Late 1930s
James Tanner, an ornithologist, was the world's greatest expert on ivory-billed woodpeckers and their behaviour. In 1935, at age twenty, he spent six months recording the calls of endangered birds. During this time, he fell in love with ivory-billeds. Very little was known about ivory-billed woodpeckers at the time--"nobody knew how many young it had, what it ate, where it lived, what it did, anything about it," explained Jim's wife Nancy. Jim spent three years travelling 48,000 miles, examining "every area where it might possibly still be." At that time, in the late 1930s, Jim estimated that "there might be possibly twenty-two ivory-billeds still left." The best place to search for them seemed to be the Singer tract, where the Cornell expedition would later report finding them. In total, Tanner estimated that 22-24 ivory-billeds remained.
Ivory-Billeds in the Early 1940s
After Jim Tanner completed his initial survey of the ivory-billeds, the Singer tract would be logged by the Chicago Mill and Lumber Company, destroying a large part of the birds' habitat. Jim "wanted to know how many were left", and so in 1940 and again in 1941 he and Nancy visited the tract, where they located a total of five birds. They took a large number of photos of them. Dismayed by the destruction of the forest and by the miniscule number of ivory-billeds that remained, James Tanner never went again. The last accepted sighting of an American ivory-billed took place in April 1944 when Don Eckelberry, a scientific illustrator, painted and sketched one. He had been sent by the National Audobon Society, a bird conservationist group who he worked for, to see whether even a single ivory-billed remained. Don Eckelberry watched for several days, but saw only a single bird. At that time, the logging of the tract was nearly complete.
Lack of Evidence of Habitation
David Sibley is perhaps the best-known birder in America. A largely self-taught naturalist, he has encyclopaedic knowledge of every bird that exists in North America, which he shares through his many massive guides to bird life and behaviour, and his field guides, which are widely considered to be the bibles of birding. Following the public announcement that an ivory-billed had been rediscovered, Sibley immediately began studying the bird (mainly from Tanner's work) and the sightings, and made arrangements to spend ten days camping in the woods close to where the bird had been sighted. The area in which he camped was the largest undisturbed patch of woods near the alleged sighting, "so it seemed like the best chance of being the source of the bird that was seen at the Cache River."
After spending ten days in the area where the bird was allegedly spotted, Sibley began to feel doubt about the bird's continued existence. Sibley noted the even in this supposedly undisturbed forest, "everywhere I went, I saw fishermen and hunters and signs of hunters. It's not some lost world sort of setting where ivory-billed woodpeckers have survived there, for sixty years, unseen." He also noted that Tanner had observed that, to eat, ivory-billeds would typically strip the bark from dead trees and fallen logs in order to consume beetle larvae hiding beneath it. Tanner had observed that their favourite tree was the Nuttall's oak. While searching the woods for ivory-billeds, it had stood out to Sibley how small the remaining forested area was. "It was that observation that really got me thinking that, if ivory-billeds are there, in that forest, they're going to have to take advantage of every dead tree that's there, because that's what they need for food. And if oaks are really their favourite tree, for the beetles that they live on, every oak that dies of old age should be peeled clean by ivory-billed woodpeckers. There was just the opposite. There was no sign that any of the bark had been peeled off those oak trees." After spending days continually searching, and seeing no signs--not a bird, not a bird-call, not a roost hole, not a single sign of ivory-billed consumption habits--Sibley began to "think seriously about the possibility that the whole thing was wrong."
Doubts from experts
Ornithologist Jerome A. Jackson is widely recognised as the foremost modern expert on ivory-billed woodpeckers, having specialised in them throughout his career. His book, In Search of the Ivory-Billed Woodpecker, published prior to the bird's alleged rediscovery, was the sole complete natural history of the ivory-billed, an in-depth examination of its behavioural ecology and of its collective life and death. When he was contacted shortly before the public announcement and told that the ivory-billed had been rediscovered, "I was ecstatic." It wasn't until the research team's scientific publications regarding the bird came out that he became convinced that the bird in the alleged video was not an ivory-billed.
He wasn't alone--Richard Prum, an evolutionary ornithologist, ornithology professor at Yale, and curator of ornithology at the Yale Peabody Museum of Natural History, had started out skeptical ("Arkansas was not where I would have imagined it would show up...I knew a few people who'd worked in the area extensively, and I wondered, you know, how come they didn't pick it up?"), and his skepticism had only grown. While handling the preserved ivory-billed specimens kept at the museum, he immediately noticed how different their colouration was from that of the bird described in the paper announcing the species' rediscovery.
Prum and Jackson began communicating about their doubts surrounding the supposed rediscovery of the woodpecker. Jackson noted that "we both felt the same way, that the extent of white on the wing of the bird in that photograph [still from the four-second video]...is too much, it's too high on the shoulder to be an ivory-billed woodpecker." They began working together to analyse the video, and ultimately found evidence that "this was not an ivory-billed. It was almost certainly a normal pileated woodpecker in that video." Prum explained that "when we measure the size of the white patch in that video, and compare it to the width of the trunk [the tree trunk beside the bird in the video], we find that the white image in the video is almost exactly the same size as the white patch on the underwing of a pileated woodpecker." Jackson concurred--"look at how much white is showing. That's the amount of white, the vast extensive white you see on the underside of the wing of a pileated woodpecker."
In 2004, Nancy Tanner was the only living person known to have seen an ivory-billed flying. No one aside from her knew what the underside of an ivory-billed woodpecker's wing looked like in flight. Despite that, she was never consulted about the tape. When she finally saw it, she found that "it didn't look particularly right in any way." (Side note, but I'm generally frustrated by the dismissive way Nancy Tanner was treated by the research team, when she had more experience with ivory-billeds than anyone else on Earth.) Nancy Tanner was skeptical of the evidence, declining an invitation to "come up there and sit in a canoe and hope the bird would fly by. I said 'thank you very much, no. When you find a roost hole, I'll be there.'"
But what about the tapes?
In response to Prum and Jackson's criticisms, John Fitzpatrick announced recordings, captured by autonomous recording units on the White River National Wildlife Refuge. He claimed those units, left by the Cornell team to capture noises made in the area, had recorded vocalisations made by the ivory-billed woodpecker. The recordings did not convince Prum and Jackson.
The only undisputed recordings of the call of the ivory-billed woodpecker were made in 1935, recorded by a bird-tracking team led by ornithologist Arthur Allen. Jackson commented that some of the calls captured by the recording device "sounded very much like the Arthur Allen vocalisations. In fact, I wondered if they weren't the Arthur Allen vocalisations." He shared his suspicion that the Arthur Allen recordings may have been used by one of the many, many birders who had flooded the forest after the woodpecker's alleged return was announced in an attempt to draw the bird out. Similarly, Prum noted that the supposed cry of the bird was captured very early in the morning, "perhaps pre-dawn", while the ivory-billed was known to be a late riser.
Both also felt that many of the sounds captured by the recording units sounded more like the similar cry of the bluejay than the cry of the ivory-billed. Some suggested that if the bluejay was making that sound, it must be mimicking ivory-billeds that were in the area, but the bluejay makes a similar cry in areas where the ivory-billed has never lived. Some of the alleged ivory-billeds calls also sounded more like a porcupine's oink or a deer's bleating.
"These are recordings," stated Jackson, "a very few recordings that have been isolated from [tens of] thousands of hours of recordings." The ivory-billed was known to call loudly and frequently in comparison to other birds. If ivory-billeds lived in the area, why were there almost no clear recordings of its cry?
An Absence of Evidence
Since the alleged rediscovery of the ivory-billed woodpecker, there have been many opportunities to gather firm evidence of their continued existence. Research teams left many cameras in the areas in Arkansas where they had purportedly been seen, but despite tens or hundreds of thousands of hours of video recordings, there was no unambiguous or even probable shot of an ivory-billed. When the ivory-billed's continued existence was reported, hundreds of bird-watchers from around the country came to search for it. Not one has ever captured a photograph of one.
The ivory-billed was not a particularly retiring bird--in fact, it was far less easily spooked by humans than many other birds in the region. Jim and Nancy Tanner captured an enormous number of close photographs of the ivory-billed with relative ease. How likely is it that hundreds of trained ornithologists would fail to capture even one? Discussing her skepticism, Nancy Tanner noted that "I thought they'd get marvelous pictures, with all those people."
Similarly, despite multiple years of searching by highly trained research teams, not a single active roost hole was found, and there were no clear encounters with ivory-billed woodpeckers. While the research team did report that they had spotted the ivory-billed fourteen times, the sightings were very distant and unclear. Tim Barksdale, a member of the 2005 search team, describing the team's alleged sightings, stated that "everyone saw the trailing edge, the general shape, but no one really saw the head well, and no one really saw the tail well at all [...] I saw this light eye in a dark head, but I didn't see the bill, I didn't see the crest, I didn't see the tail."
When Prum was asked what evidence he and Jackson would need to believe that the bird continued to exist, he replied "what we need is for two people to tell me they saw the bird perched and it knocked on the wood, and it turned its head [...] and they saw the bill. Just like what any kind of bird-watching event is. You see the bird!"
Since the April 2005 announcement, sightings of the bird have been reported in many states besides Arkansas, particularly Louisiana, Florida, and Mississippi (as well as in many states and countries where the ivory-billed had no known historic presence.) Despite that, in these last sixteen years, not a single ivory-billed has been found, anywhere.
Why does it matter?
The ivory-billed woodpecker is almost certainly extinct. Even if a miniscule number of individual birds remain alive, which in my view is staggeringly unlikely, the woodpecker is still extinct in every meaningful sense. There simply aren't enough remaining birds for them to breed with one another and continue their species. There are real birds, who we know to be alive, who are in grave danger now for the same reasons that the ivory-billed was in grave danger in the 1930s. Only now, when it is too late to help the ivory-billed in any meaningful sense, do we start paying attention. The American government took millions of dollars of funding to help wildlife away from animals that certainly exist, to spend on a futile attempt to preserve what's essentially a cryptid.
In 2009, as people were searching the woods for a bird last spotted in 1944, there were 3,000 kirtland's warblers left, 373 wild whooping cranes, 127 wild California condors, and 50 wild Attwaters prairie chickens. Why have many of us heard of the ivory-billed, but not heard of those birds? Will people act now to save these birds, or will we ignore them for decades until they're thought extinct, and then pore over blurry photos from someone's backyard purporting to show that they aren't really extinct after all, that we didn't really slaughter them?
David Sibley remarked that "if you bring up ivory-billed woodpeckers at all, it turns into a debate of hope vs. skepticism. It takes emphasis away from the fundamental problem--that we destroyed all of the ivory-billeds' habitat, and we really haven't changed the way we treat the land that much. We're still cutting down forests and ploughing up sagebrush, and other species are at risk."
In conclusion
It would be a wonderful thing if the ivory-billed woodpecker were still alive. But the reality is that it isn't. It's too late for us to help the ivory-billed, but it's not too late to help other animals in danger of the same fate. Donate to and volunteer with nature conservation groups in your area, to help stop other species from experiencing what the last ivory-billeds did.
Sources
In Search of the Ivory-Billed Woodpecker by Jerome A. Jackson (now with an afterword disputing the alleged rediscovery)
The Ivory-Billed Woodpecker by James T. Tanner
Ghost Bird (2009), a phenomenal documentary that's available on Kanopy and from which I got most of these quotes
There have been persistent rumours, discussed on this subreddit, that perhaps the ivory-billed woodpecker still exists in America. In 2004, an alleged sighting in Arkansas sparked significant academic interest in the continued existence of the bird. Researchers from the Cornell Laboratory of Ornithology, led by John Fitzpatrick, investigated the woods where the bird was allegedly spotted, producing recordings of possible ivory-billed calls and knocks, and a four-second video that they claimed captured an ivory-billed woodpecker. Following this, the researchers publicly announced that the ivory-billed continued to exist, sparking academic debate, and many searches for the bird. In this post, I will explain why the ivory-billed woodpecker is in fact extinct, and why it matters.
Ivory-Billeds in the Late 1930s
James Tanner, an ornithologist, was the world's greatest expert on ivory-billed woodpeckers and their behaviour. In 1935, at age twenty, he spent six months recording the calls of endangered birds. During this time, he fell in love with ivory-billeds. Very little was known about ivory-billed woodpeckers at the time--"nobody knew how many young it had, what it ate, where it lived, what it did, anything about it," explained Jim's wife Nancy. Jim spent three years travelling 48,000 miles, examining "every area where it might possibly still be." At that time, in the late 1930s, Jim estimated that "there might be possibly twenty-two ivory-billeds still left." The best place to search for them seemed to be the Singer tract, where the Cornell expedition would later report finding them. In total, Tanner estimated that 22-24 ivory-billeds remained.
Ivory-Billeds in the Early 1940s
After Jim Tanner completed his initial survey of the ivory-billeds, the Singer tract would be logged by the Chicago Mill and Lumber Company, destroying a large part of the birds' habitat. Jim "wanted to know how many were left", and so in 1940 and again in 1941 he and Nancy visited the tract, where they located a total of five birds. They took a large number of photos of them. Dismayed by the destruction of the forest and by the miniscule number of ivory-billeds that remained, James Tanner never went again. The last accepted sighting of an American ivory-billed took place in April 1944 when Don Eckelberry, a scientific illustrator, painted and sketched one. He had been sent by the National Audobon Society, a bird conservationist group who he worked for, to see whether even a single ivory-billed remained. Don Eckelberry watched for several days, but saw only a single bird. At that time, the logging of the tract was nearly complete.
Lack of Evidence of Habitation
David Sibley is perhaps the best-known birder in America. A largely self-taught naturalist, he has encyclopaedic knowledge of every bird that exists in North America, which he shares through his many massive guides to bird life and behaviour, and his field guides, which are widely considered to be the bibles of birding. Following the public announcement that an ivory-billed had been rediscovered, Sibley immediately began studying the bird (mainly from Tanner's work) and the sightings, and made arrangements to spend ten days camping in the woods close to where the bird had been sighted. The area in which he camped was the largest undisturbed patch of woods near the alleged sighting, "so it seemed like the best chance of being the source of the bird that was seen at the Cache River."
After spending ten days in the area where the bird was allegedly spotted, Sibley began to feel doubt about the bird's continued existence. Sibley noted the even in this supposedly undisturbed forest, "everywhere I went, I saw fishermen and hunters and signs of hunters. It's not some lost world sort of setting where ivory-billed woodpeckers have survived there, for sixty years, unseen." He also noted that Tanner had observed that, to eat, ivory-billeds would typically strip the bark from dead trees and fallen logs in order to consume beetle larvae hiding beneath it. Tanner had observed that their favourite tree was the Nuttall's oak. While searching the woods for ivory-billeds, it had stood out to Sibley how small the remaining forested area was. "It was that observation that really got me thinking that, if ivory-billeds are there, in that forest, they're going to have to take advantage of every dead tree that's there, because that's what they need for food. And if oaks are really their favourite tree, for the beetles that they live on, every oak that dies of old age should be peeled clean by ivory-billed woodpeckers. There was just the opposite. There was no sign that any of the bark had been peeled off those oak trees." After spending days continually searching, and seeing no signs--not a bird, not a bird-call, not a roost hole, not a single sign of ivory-billed consumption habits--Sibley began to "think seriously about the possibility that the whole thing was wrong."
Doubts from experts
Ornithologist Jerome A. Jackson is widely recognised as the foremost modern expert on ivory-billed woodpeckers, having specialised in them throughout his career. His book, In Search of the Ivory-Billed Woodpecker, published prior to the bird's alleged rediscovery, was the sole complete natural history of the ivory-billed, an in-depth examination of its behavioural ecology and of its collective life and death. When he was contacted shortly before the public announcement and told that the ivory-billed had been rediscovered, "I was ecstatic." It wasn't until the research team's scientific publications regarding the bird came out that he became convinced that the bird in the alleged video was not an ivory-billed.
He wasn't alone--Richard Prum, an evolutionary ornithologist, ornithology professor at Yale, and curator of ornithology at the Yale Peabody Museum of Natural History, had started out skeptical ("Arkansas was not where I would have imagined it would show up...I knew a few people who'd worked in the area extensively, and I wondered, you know, how come they didn't pick it up?"), and his skepticism had only grown. While handling the preserved ivory-billed specimens kept at the museum, he immediately noticed how different their colouration was from that of the bird described in the paper announcing the species' rediscovery.
Prum and Jackson began communicating about their doubts surrounding the supposed rediscovery of the woodpecker. Jackson noted that "we both felt the same way, that the extent of white on the wing of the bird in that photograph [still from the four-second video]...is too much, it's too high on the shoulder to be an ivory-billed woodpecker." They began working together to analyse the video, and ultimately found evidence that "this was not an ivory-billed. It was almost certainly a normal pileated woodpecker in that video." Prum explained that "when we measure the size of the white patch in that video, and compare it to the width of the trunk [the tree trunk beside the bird in the video], we find that the white image in the video is almost exactly the same size as the white patch on the underwing of a pileated woodpecker." Jackson concurred--"look at how much white is showing. That's the amount of white, the vast extensive white you see on the underside of the wing of a pileated woodpecker."
In 2004, Nancy Tanner was the only living person known to have seen an ivory-billed flying. No one aside from her knew what the underside of an ivory-billed woodpecker's wing looked like in flight. Despite that, she was never consulted about the tape. When she finally saw it, she found that "it didn't look particularly right in any way." (Side note, but I'm generally frustrated by the dismissive way Nancy Tanner was treated by the research team, when she had more experience with ivory-billeds than anyone else on Earth.) Nancy Tanner was skeptical of the evidence, declining an invitation to "come up there and sit in a canoe and hope the bird would fly by. I said 'thank you very much, no. When you find a roost hole, I'll be there.'"
But what about the tapes?
In response to Prum and Jackson's criticisms, John Fitzpatrick announced recordings, captured by autonomous recording units on the White River National Wildlife Refuge. He claimed those units, left by the Cornell team to capture noises made in the area, had recorded vocalisations made by the ivory-billed woodpecker. The recordings did not convince Prum and Jackson.
The only undisputed recordings of the call of the ivory-billed woodpecker were made in 1935, recorded by a bird-tracking team led by ornithologist Arthur Allen. Jackson commented that some of the calls captured by the recording device "sounded very much like the Arthur Allen vocalisations. In fact, I wondered if they weren't the Arthur Allen vocalisations." He shared his suspicion that the Arthur Allen recordings may have been used by one of the many, many birders who had flooded the forest after the woodpecker's alleged return was announced in an attempt to draw the bird out. Similarly, Prum noted that the supposed cry of the bird was captured very early in the morning, "perhaps pre-dawn", while the ivory-billed was known to be a late riser.
Both also felt that many of the sounds captured by the recording units sounded more like the similar cry of the bluejay than the cry of the ivory-billed. Some suggested that if the bluejay was making that sound, it must be mimicking ivory-billeds that were in the area, but the bluejay makes a similar cry in areas where the ivory-billed has never lived. Some of the alleged ivory-billeds calls also sounded more like a porcupine's oink or a deer's bleating.
"These are recordings," stated Jackson, "a very few recordings that have been isolated from [tens of] thousands of hours of recordings." The ivory-billed was known to call loudly and frequently in comparison to other birds. If ivory-billeds lived in the area, why were there almost no clear recordings of its cry?
An Absence of Evidence
Since the alleged rediscovery of the ivory-billed woodpecker, there have been many opportunities to gather firm evidence of their continued existence. Research teams left many cameras in the areas in Arkansas where they had purportedly been seen, but despite tens or hundreds of thousands of hours of video recordings, there was no unambiguous or even probable shot of an ivory-billed. When the ivory-billed's continued existence was reported, hundreds of bird-watchers from around the country came to search for it. Not one has ever captured a photograph of one.
The ivory-billed was not a particularly retiring bird--in fact, it was far less easily spooked by humans than many other birds in the region. Jim and Nancy Tanner captured an enormous number of close photographs of the ivory-billed with relative ease. How likely is it that hundreds of trained ornithologists would fail to capture even one? Discussing her skepticism, Nancy Tanner noted that "I thought they'd get marvelous pictures, with all those people."
Similarly, despite multiple years of searching by highly trained research teams, not a single active roost hole was found, and there were no clear encounters with ivory-billed woodpeckers. While the research team did report that they had spotted the ivory-billed fourteen times, the sightings were very distant and unclear. Tim Barksdale, a member of the 2005 search team, describing the team's alleged sightings, stated that "everyone saw the trailing edge, the general shape, but no one really saw the head well, and no one really saw the tail well at all [...] I saw this light eye in a dark head, but I didn't see the bill, I didn't see the crest, I didn't see the tail."
When Prum was asked what evidence he and Jackson would need to believe that the bird continued to exist, he replied "what we need is for two people to tell me they saw the bird perched and it knocked on the wood, and it turned its head [...] and they saw the bill. Just like what any kind of bird-watching event is. You see the bird!"
Since the April 2005 announcement, sightings of the bird have been reported in many states besides Arkansas, particularly Louisiana, Florida, and Mississippi (as well as in many states and countries where the ivory-billed had no known historic presence.) Despite that, in these last sixteen years, not a single ivory-billed has been found, anywhere.
Why does it matter?
The ivory-billed woodpecker is almost certainly extinct. Even if a miniscule number of individual birds remain alive, which in my view is staggeringly unlikely, the woodpecker is still extinct in every meaningful sense. There simply aren't enough remaining birds for them to breed with one another and continue their species. There are real birds, who we know to be alive, who are in grave danger now for the same reasons that the ivory-billed was in grave danger in the 1930s. Only now, when it is too late to help the ivory-billed in any meaningful sense, do we start paying attention. The American government took millions of dollars of funding to help wildlife away from animals that certainly exist, to spend on a futile attempt to preserve what's essentially a cryptid.
In 2009, as people were searching the woods for a bird last spotted in 1944, there were 3,000 kirtland's warblers left, 373 wild whooping cranes, 127 wild California condors, and 50 wild Attwaters prairie chickens. Why have many of us heard of the ivory-billed, but not heard of those birds? Will people act now to save these birds, or will we ignore them for decades until they're thought extinct, and then pore over blurry photos from someone's backyard purporting to show that they aren't really extinct after all, that we didn't really slaughter them?
David Sibley remarked that "if you bring up ivory-billed woodpeckers at all, it turns into a debate of hope vs. skepticism. It takes emphasis away from the fundamental problem--that we destroyed all of the ivory-billeds' habitat, and we really haven't changed the way we treat the land that much. We're still cutting down forests and ploughing up sagebrush, and other species are at risk."
In conclusion
It would be a wonderful thing if the ivory-billed woodpecker were still alive. But the reality is that it isn't. It's too late for us to help the ivory-billed, but it's not too late to help other animals in danger of the same fate. Donate to and volunteer with nature conservation groups in your area, to help stop other species from experiencing what the last ivory-billeds did.
Sources
In Search of the Ivory-Billed Woodpecker by Jerome A. Jackson (now with an afterword disputing the alleged rediscovery)
The Ivory-Billed Woodpecker by James T. Tanner
Ghost Bird (2009), a phenomenal documentary that's available on Kanopy and from which I got most of these quotes
