Chihuahuan Raven
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| Chihuahuan Raven | ||||||||||||||
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| Corvus cryptoleucus Couch, 1854 |
The Chihuahuan Raven (Corvus cryptoleucus), formerly known as the American White-necked Raven, has the proportions of a Common Raven with a heavy bill, but is about the same size as a Carrion Crow, or slightly larger (44-51 cm in length) than the American Crow. The plumage is all-black with a rich purple-blue gloss in good light. The nasal bristles extend farther down the top of the bill than in any other Corvus species to about two-thirds the length. The base of the neck feathers are white (seen only when ruffled in strong wind). The bill, legs and feet are black.
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[edit] Distribution and habitat
It occurs in the southwestern United States and Mexico including southeastern Arizona, southern New Mexico, northeastern Colorado, central and southern Nebraska and, in Mexico.
[edit] Behaviour
[edit] Diet
It feeds on cultivated cereal grains, insects and many other invertebrates, small reptiles, carrion and scraps of human food, cactus fruits, eggs and nestlings.
[edit] Nesting
The nest is built in either trees, large shrubs or sometimes even in old buildings. There are usually 5-7 eggs laid relatively late in the year during May so as to take advantage of the insect food for their young in their more arid environment.
[edit] Voice
The voice is similar to the Common Raven with "pruk-pruk" sounds and other croaks but is not as deep in tone or as varied in range.
[edit] Taxonomy
A 2005 molecular study reviewed segments of DNA of the Common Raven and found the Chihuahuan Raven are genetically nested within Common Ravens based on mitochondrial DNA. That is Common Ravens from the California Clade are more similar in mtDNA to Chihuahuan Ravens than they are to Common Ravens in the Holarctic Clade.[1] (also see Omland et al. 2000 -- Omland, K. E., C. L. Tarr, W. I. Boarman, J. M. Marzluff, and R. C. Fleischer. 2000. Cryptic genetic variation and paraphyly in ravens. Proceedings of the Royal Society Biological Sciences Series B 267:2475-2482.)
[edit] References
- ^ Feldman CR, Omland KE (2005) Phylogenetics of the common raven complex (Corvus: Corvidae) and the utility of ND4, COI and intron 7 of the β-fibrinogen gene in avian molecular systematics. Zoologica Scripta 34 145
- BirdLife International (2004). Corvus cryptoleucus. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006. Database entry includes justification for why this species is of least concern
Omland, K. E., C. L. Tarr, W. I. Boarman, J. M. Marzluff, and R. C. Fleischer. 2000. Cryptic genetic variation and paraphyly in ravens. Proceedings of the Royal Society Biological Sciences Series B 267:2475-2482.
[edit] External links
- Photo of Chihuahuan Raven
- Great shot showing white bases to neck feathers
- Comparison of Chihuahuan and Common Raven specimens
- Patuxent Bird Identification InfoCenter species account, including Breeding Bird Survey and Christmas Bird Count range maps.
- Chihuahuan Raven photo gallery VIREO
