Female Imperial Woodpecker mounted and photographed in 2007, now at the Indiana State Museum and formerly thought to be an Ivory-Billed Woodpecker. Imperial Woodpeckers usually live in Mexico and so the sight of such an unusual bird here is doubly jolting.
Imperial, Ivory-Billed and Pileated Woodpeckers [The Males]
Similar Field Guide Comparison for Mexico.
http://en.wikipedia.org/wiki/Imperial_Woodpecker
Imperial Woodpecker
From Wikipedia, the free encyclopedia
The Imperial Woodpecker (Campephilus imperialis) is – or was – a member of the woodpecker family Picidae. If it is not extinct, it is the world's largest woodpecker species at 56-60 cm (22-24 in) long.[1] Due to its close relationship and similarity to the Ivory-billed Woodpecker, it is sometimes also called "Mexican Ivorybill" but this name is also used for the Pale-billed Woodpecker. The large and conspicuous bird has for long been known to the native inhabitants of Mexico and was called cuauhtotomomi in Nahuatl, uagam by the Tepehuán, and cumecócari by the Tarahumara
Description and ecology
The male had a red-sided crest, but was otherwise black, apart from the inner primaries, which were white-tipped, white secondaries, and a white scapular stripe which unlike in the Ivory-billed Woodpecker did not extend on the neck. The female was similar but the crest was all black and (unlike the Ivorybill) recurved at the top. It was once widespread and, until the early 1950s, not uncommon throughout the Sierra Madre Occidental of Mexico, from western Sonora and Chihuahua southwards to Jalisco and Michoacan.
It preferred open montane forests made up of Durango, Mexican White, Loblolly and Montezuma Pines and oak, usually between 2100 and 2700 meters ASL. It fed mainly by scaling bark from dead pine trees and feeding on the insect larvae found underneath. A mating pair required a very large area of untouched mature forest to survive, approximately 26 km² (10 square miles); outside the breeding season, the birds apparently formed small groups of a handful to a dozen individuals and moved about a wider area, apparently in response to availability of food (Lammertink et al., 1996).
Decline and probable extinction
The Imperial Woodpecker is officially listed as Critically Endangered (possibly extinct) by the IUCN and BirdLife International. However, the last confirmed report was of a recently-shot bird in Durango in 1956 and the species is probably now extinct. The primary reason for its decline was loss of habitat, although the decline was also accelerated by over-hunting for use in folk medicine and because nestlings were considered a delicacy at least by the Tarahumara. Imperial Woodpeckers were stunning birds and as the species became rare many were apparently shot by people who had never encountered such a bird and wanted to get a closer look (Lammertink et al., 1996).
Given the near total destruction of its original habitat, and the lack of any confirmed sightings in over 50 years, most ornithologists believe the Imperial Woodpecker must be extinct. There are a handful of more recent, unconfirmed sightings (Mendenhall, 2005), the most recent of which closely followed the 2005 publication of the purported rediscovery of the Ivory-billed Woodpecker. Lammertink et al. (1996), after extensively reviewing post-1956 reports, conclude that the species did indeed survive into the 1990s in the central part of its range but also consider a continued survival very unlikely. According to them, the population was always restricted in historic times, although the species was indeed present in maximum density before a catastrophic decline during the 1950s. The lack of good records during that time is apparently more based on lack of research than on actual rarity, but this seems to have changed radically only one decade later.
The Imperial Woodpecker is known from about 120 museum specimens; unlike the Ivory-billed Woodpecker, no photographs or recordings of living birds are known to exist. However one bird was filmed flying in 1953, and Cornell University is said to be in possession of a copy (Dalton 2005), though it has not been made public.
See also Ivory-billed Woodpecker
http://en.wikipedia.org/wiki/Ivory-billed_Woodpecker
References
BirdLife International (2004). Campephilus imperialis. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 9 May 2006. Database entry includes a range map and justification for why this species is possibly extinct
Casillas-Orona, Federico Moctezuma (2005): The Imperial Woodpecker, Campephilus imperialis (Gould, 1832). Short paper published online; June, 2005. PDF fulltext
Dalton, Rex (2005): Ornithology: A wing and a prayer. Nature 437(8 September 2005): 188–190. Summary
Lammertink, M.; Rojas-Tomé, J.A.; Casillas-Orona, F.M. & Otto, R.L. (1996): Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre Occidental, Mexico. Verslagen en Technische Gegevens Instituut voor Systematiek en Populatiebiologie (Zoologisch Museum) 69: 1–89. HTML fulltext
Mendenhall, Matt (2005): Old Friend Missing. Birder's World 2005(6): 35–39. HTML fulltext
Tanner, James T. (1964): The Decline and Present Status of the Imperial Woodpecker of Mexico. Auk 81(1): 74–81. PDF fulltext
[edit] External linksBirdLife Species Factsheet
3D view of specimen RMNH 110.098, Naturalis, Leiden – requires QuickTime browser plugin)
1.^ http://www.birdlife.org/datazone/speciesfactsheet.php?id=718
It is my hypothesis that the large bird seen by Phillip O'Donnell and others and thought by them to represent a small Pteranodon was instead a gigantic woodpecker. This viewpoint is not shared by the witnesses and they should not be construed as going along with my identification. My idea was that it could be an outsized Imperial Woodpecker in an unexpected range far to the North of their usual range in Western Mexico. It might sit up three feet tall or more and with a possible maximum wingspan of five feet plus or minus - these being gigantic specimens and perhaps well above the average for the species. The witnesses said it was as big as an eagle and I see no reason to slight them on that.
Usual Range For Imperial Woodpecker.
Map for typical range of Pileated Woodpeckers plus red squares added for the unusual outsized-outrange Impies. The one at the Indiana State Museum is labelled a vagrant but no doubt came originally from further south.
The series of reports from Northern California-Oregon and surrounding regions appear as birds of very large size and very exaggerated crests.
Scale Comparison: at Right, Ivory-Billed (top) and Pileated woodpeckers (bottom), centre a turkey vulture as a size comparison and at left mock-ups for Greater-Imperial woodpeckers using a modified ivory-billed woodpecker photo as a base - at top, larger than usual imperial as the average base for the proposed cryptid category, and at bottom, gigantic (freakish) individual to be more in line with the reports. Note that the tail is also unusually elongated, another feature of such reports.
Incidentally my earlier statement on the continuance of Ivory-Billed woodpeckers remains valid: there is a subspecies of Ivory-billed woodpecker on Cuba that nobody insists must be extinct. Such birds could very easily fly over to Florida and re-establish themselves there. So in my opinion the whole argument is a lot of hogwash when various authorities insist ivorybills "must" be extinct or witnesses "must" be seeing pileated woodpeckers instead. There is no "must" about it. And just coincidentally, a Pileated woodpecker lives in the tree outside my back room library window and it has been so close outside that I could have opened the window and touched it before.
Best Wishes, Dale D.
Imperial, Ivory-Billed and Pileated Woodpeckers [The Males]
Similar Field Guide Comparison for Mexico.
http://en.wikipedia.org/wiki/Imperial_Woodpecker
Imperial Woodpecker
From Wikipedia, the free encyclopedia
The Imperial Woodpecker (Campephilus imperialis) is – or was – a member of the woodpecker family Picidae. If it is not extinct, it is the world's largest woodpecker species at 56-60 cm (22-24 in) long.[1] Due to its close relationship and similarity to the Ivory-billed Woodpecker, it is sometimes also called "Mexican Ivorybill" but this name is also used for the Pale-billed Woodpecker. The large and conspicuous bird has for long been known to the native inhabitants of Mexico and was called cuauhtotomomi in Nahuatl, uagam by the Tepehuán, and cumecócari by the Tarahumara
Description and ecology
The male had a red-sided crest, but was otherwise black, apart from the inner primaries, which were white-tipped, white secondaries, and a white scapular stripe which unlike in the Ivory-billed Woodpecker did not extend on the neck. The female was similar but the crest was all black and (unlike the Ivorybill) recurved at the top. It was once widespread and, until the early 1950s, not uncommon throughout the Sierra Madre Occidental of Mexico, from western Sonora and Chihuahua southwards to Jalisco and Michoacan.
It preferred open montane forests made up of Durango, Mexican White, Loblolly and Montezuma Pines and oak, usually between 2100 and 2700 meters ASL. It fed mainly by scaling bark from dead pine trees and feeding on the insect larvae found underneath. A mating pair required a very large area of untouched mature forest to survive, approximately 26 km² (10 square miles); outside the breeding season, the birds apparently formed small groups of a handful to a dozen individuals and moved about a wider area, apparently in response to availability of food (Lammertink et al., 1996).
Decline and probable extinction
The Imperial Woodpecker is officially listed as Critically Endangered (possibly extinct) by the IUCN and BirdLife International. However, the last confirmed report was of a recently-shot bird in Durango in 1956 and the species is probably now extinct. The primary reason for its decline was loss of habitat, although the decline was also accelerated by over-hunting for use in folk medicine and because nestlings were considered a delicacy at least by the Tarahumara. Imperial Woodpeckers were stunning birds and as the species became rare many were apparently shot by people who had never encountered such a bird and wanted to get a closer look (Lammertink et al., 1996).
Given the near total destruction of its original habitat, and the lack of any confirmed sightings in over 50 years, most ornithologists believe the Imperial Woodpecker must be extinct. There are a handful of more recent, unconfirmed sightings (Mendenhall, 2005), the most recent of which closely followed the 2005 publication of the purported rediscovery of the Ivory-billed Woodpecker. Lammertink et al. (1996), after extensively reviewing post-1956 reports, conclude that the species did indeed survive into the 1990s in the central part of its range but also consider a continued survival very unlikely. According to them, the population was always restricted in historic times, although the species was indeed present in maximum density before a catastrophic decline during the 1950s. The lack of good records during that time is apparently more based on lack of research than on actual rarity, but this seems to have changed radically only one decade later.
The Imperial Woodpecker is known from about 120 museum specimens; unlike the Ivory-billed Woodpecker, no photographs or recordings of living birds are known to exist. However one bird was filmed flying in 1953, and Cornell University is said to be in possession of a copy (Dalton 2005), though it has not been made public.
See also Ivory-billed Woodpecker
http://en.wikipedia.org/wiki/Ivory-billed_Woodpecker
References
BirdLife International (2004). Campephilus imperialis. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 9 May 2006. Database entry includes a range map and justification for why this species is possibly extinct
Casillas-Orona, Federico Moctezuma (2005): The Imperial Woodpecker, Campephilus imperialis (Gould, 1832). Short paper published online; June, 2005. PDF fulltext
Dalton, Rex (2005): Ornithology: A wing and a prayer. Nature 437(8 September 2005): 188–190. Summary
Lammertink, M.; Rojas-Tomé, J.A.; Casillas-Orona, F.M. & Otto, R.L. (1996): Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre Occidental, Mexico. Verslagen en Technische Gegevens Instituut voor Systematiek en Populatiebiologie (Zoologisch Museum) 69: 1–89. HTML fulltext
Mendenhall, Matt (2005): Old Friend Missing. Birder's World 2005(6): 35–39. HTML fulltext
Tanner, James T. (1964): The Decline and Present Status of the Imperial Woodpecker of Mexico. Auk 81(1): 74–81. PDF fulltext
[edit] External linksBirdLife Species Factsheet
3D view of specimen RMNH 110.098, Naturalis, Leiden – requires QuickTime browser plugin)
1.^ http://www.birdlife.org/datazone/speciesfactsheet.php?id=718
It is my hypothesis that the large bird seen by Phillip O'Donnell and others and thought by them to represent a small Pteranodon was instead a gigantic woodpecker. This viewpoint is not shared by the witnesses and they should not be construed as going along with my identification. My idea was that it could be an outsized Imperial Woodpecker in an unexpected range far to the North of their usual range in Western Mexico. It might sit up three feet tall or more and with a possible maximum wingspan of five feet plus or minus - these being gigantic specimens and perhaps well above the average for the species. The witnesses said it was as big as an eagle and I see no reason to slight them on that.
Usual Range For Imperial Woodpecker.
Map for typical range of Pileated Woodpeckers plus red squares added for the unusual outsized-outrange Impies. The one at the Indiana State Museum is labelled a vagrant but no doubt came originally from further south.
The series of reports from Northern California-Oregon and surrounding regions appear as birds of very large size and very exaggerated crests.
Scale Comparison: at Right, Ivory-Billed (top) and Pileated woodpeckers (bottom), centre a turkey vulture as a size comparison and at left mock-ups for Greater-Imperial woodpeckers using a modified ivory-billed woodpecker photo as a base - at top, larger than usual imperial as the average base for the proposed cryptid category, and at bottom, gigantic (freakish) individual to be more in line with the reports. Note that the tail is also unusually elongated, another feature of such reports.
Incidentally my earlier statement on the continuance of Ivory-Billed woodpeckers remains valid: there is a subspecies of Ivory-billed woodpecker on Cuba that nobody insists must be extinct. Such birds could very easily fly over to Florida and re-establish themselves there. So in my opinion the whole argument is a lot of hogwash when various authorities insist ivorybills "must" be extinct or witnesses "must" be seeing pileated woodpeckers instead. There is no "must" about it. And just coincidentally, a Pileated woodpecker lives in the tree outside my back room library window and it has been so close outside that I could have opened the window and touched it before.
Best Wishes, Dale D.
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