Imperial woodpecker

Imperial woodpecker
Male and female specimens

Critically endangered, possibly extinct  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Piciformes
Family: Picidae
Genus: Campephilus
Species: C. imperialis
Binomial name
Campephilus imperialis
(Gould, 1832)

The imperial woodpecker (Campephilus imperialis) is a member of the woodpecker family, Picidae. The genus Campephilus is essentially a tropical one, embracing 13 species, including the imperial woodpecker. If it is not extinct, it is the world's largest woodpecker species, at 56–60 cm (22–24 in) long.[2] Researchers have discovered that the imperial woodpecker has slow climbing strides and a fast wing-flap rate compared with other woodpeckers. Owing to its close taxonomic relationship, and a similarity in appearance, to the ivory-billed woodpecker, it is sometimes called the Mexican ivorybill, but this name is also used for the pale-billed woodpecker. The large and conspicuous bird has 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

Turnaround video of a male study skin, Naturalis Biodiversity Center

The imperial woodpeckers typical size ranges from 56 to 60 cm, an enormous, stunning black-and-white woodpecker. The male imperial woodpecker has a red-sided crest, centered black, but otherwise mostly black, with large white wing-patch, thin white "braces" on its mantle and a huge ivory bill. They are all black except for the inner primaries, which are white-tipped, the white secondaries, and a white scapular stripe which, unlike the ivory-billed woodpecker, does not extend onto the neck. The female is similar, but her crest is all black and (unlike the female ivorybill) recurved at the top, lacking red. Much larger than any other sympatric woodpecker, it is the only woodpecker in the area with solid black underparts. Its voice is reportedly toy-trumpet-like. The bird 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 Michoacán. There is a chance that imperialis followed the mountain region northward into southern Arizona.

The imperial woodpecker prefers open montane forests made up of Durango, Mexican white, loblolly and Montezuma pines, as well as oak, usually between 2100 and 2700 meters above sea level. Most records are from elevations of 1,920-3,050 m, but there are records as low as 1,675 m. It feeds mainly on bark scaled from dead pine trees and feeding on the insect larvae found underneath. There are many reports of more than four individuals, and this grouping behaviour may be related to its foraging specialisation. Breeding has been recorded between February and June, and probably 1-4 eggs are laid. A mated pair requires a very large area of untouched mature forest to survive, approximately 26 km2 (10 sq mi); outside the breeding season, the birds are reported to form small groups of up to a dozen individuals and move about a wide area, apparently in response to the availability of food.[3] The main food source, beetle larvae in snags, is probably distributed in patches and peaks within a short period of time. Consequently, feeding-sites are probably best exploited by "nomadic" groups. If operating in groups of seven or eight individuals, the minimum area of old-growth forest for a group is 98 km2.

The Cornell Lab of Ornithology has released a film of the woodpecker, recorded in Mexico in 1956.[4]

Decline and probable extinction

Adult male (front) and female (back)

The imperial woodpecker is officially listed as "critically endangered (possibly extinct)" by the IUCN and BirdLife International. It was not historically a rare species within a suitable habitat, but the total population probably never numbered more than 8,000 individuals (Lammertink et al. 1996). Any remaining population is assumed to be tiny (numbering fewer than 50 mature individuals) based on the lack of confirmed records since 1956; analyses of remaining habitats indicate that no tracts remain which are large enough to support the species.The last confirmed record was from Durango in 1956, and the species is very likely now extinct. If they have gone extinct, it would have been due to habitat deconstruction and fragmentation combined with hunting. These factors are the reason why the species has not been seen in over 50 years, although there have been local reports of sightings. Researchers believe that their decline was also accelerated by active eradication campaigns conducted by logging interests, by over-hunting — for use in folk medicine, and because nestlings were considered a delicacy by the Tarahumara. It has been hunted for sport, food and for medicinal purposes over a long period of time, and feathers and bills were reportedly used in rituals by Tepheuana and Huichol tribes in the south of Durango. Additionally, imperial woodpeckers are stunning birds, and as the species became increasingly rare, many were apparently shot by people who had never encountered such a bird, and wanted to get a closer look.[3][5]

Female specimen at Museum für Naturkunde Berlin; note hand for size comparison

The habitat in which the imperial woodpecker was located was predominantly in coniferous forests (terrain levels at 2,700-2,900 m. elevation). The area in which they lived was abundant with large dead trees which could be linked to their extinction. The area had been cleared and logged multiple times by 2010. Increasing effort in conservation biology is being devoted to the analysis of the extinction risk as well as the search for the rare, long unseen, species. There are a handful of more recent, unconfirmed sightings,[6] 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 from that time is apparently based more on lack of research than on actual rarity, but this seems to have changed radically only one decade later.[3]

Recent field research by Tim Gallagher and Martjan Lammertink has found evidence — in the form of accounts by elderly residents in the bird's range, who saw imperial woodpeckers decades earlier, and who discussed their recollections with the researchers — that foresters working with Mexican logging companies in the 1950s told the local people that the woodpeckers were destroying valuable timber, and encouraged the people to kill the birds. As part of this campaign, the foresters gave the local residents poison to smear on trees that the birds foraged on. Because groups of imperial woodpeckers tended to feed on a single huge, dead, old-growth pine tree for as long as two weeks, applying poison to such a tree would be an effective way to wipe out a group of up to a dozen of these huge woodpeckers — and, perhaps, even to kill off succeeding groups of the birds that might move in to the area, and be attracted to the same tree. Gallagher suspects that such a campaign of poisoning may be the key to the species' apparent catastrophic population crash in the 1950s, which has hitherto lacked a satisfactory explanation. A campaign of poisoning could well have killed whole groups of the bird in a short time. The premise of protecting valuable timber from the woodpeckers was, in fact, baseless. Imperial woodpeckers do not forage on, or excavate nest or roosting holes in live, healthy trees.[7][8]

In Gallagher's recent novel, The Grail Bird, in 2006, he discusses how difficult the search is for the imperial woodpecker due to its dangerous location. In Mexico's Sierra Madre Occidental, there are major marijuana and poppy-growing regions that are patrolled by armed guards. The drug cartels often kill anyone who comes close to their crops.[7] Gallagher's inspiration to search for the imperial woodpecker, was the discovery of a 1956 film by dentist William Rhein, who made several trips to Mexico in search of the imperial woodpecker. This is the only known photographic record of the species.[9]

The imperial woodpecker is known from about 160 museum specimens and a single amateur film from 1956 depicting one bird climbing, foraging and flying. The film has been restored and released by Cornell University.[10]

See also

Wikimedia Commons has media related to Campephilus imperialis.

References

  1. ↑ BirdLife International (2013). "Campephilus imperialis". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
  2. ↑ "Imperial Woodpecker Campephilus imperialis". BirdLife International.
  3. 1 2 3 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.
  4. ↑ Leslie Kaufman (October 28, 2011). "A Riveting Glimpse of a Vanished Bird". The New York Times.
  5. ↑ Tim Gallagher (2013): Imperial Dreams: Tracking the Imperial Woodpecker Through the Wild Sierra Madre, pp. 224-26. New York: Atria Books. ISBN 978-1-4391-9152-1.
  6. ↑ Mendenhall, Matt (2005). "Old Friend Missing". Birder's World 2005 (6): 35–39.
  7. 1 2 Gallagher: Imperial Dreams, pp. 224-26.
  8. ↑ Gallagher: Imperial Dreams, pp. 46, 54, 95, 139, 151, 225, 232.
  9. ↑ Gallagher: Imperial Dreams, pp. 225-26.
  10. ↑ Lammertink, Martjan; Gallagher, Tim W., Rosenberg, Kenneth V., Fitzpatrick, John W., Liner, Eric; Rojas-Tomé, Jorge & Escalante, Patricia (2011). "Film Documentation of the Probably Extinct Imperial Woodpecker (Campephilus imperialis)" (PDF). Auk 128 (4): 671–677. doi:10.1525/auk.2011.10271.

Further reading

External links

Wikimedia Commons has media related to Campephilus imperialis.
Wikispecies has information related to: Campephilus imperialis

Dr. William L. Rhein, film 1 http://macaulaylibrary.org/video/461027

Dr. William L. Rhein, film 2 http://macaulaylibrary.org/video/468599

Dr. William L. Rhein, film 3 http://macaulaylibrary.org/video/468600

Dr. William L. Rhein, film 4 http://macaulaylibrary.org/video/468601

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