From Opus

Photo by IanF
Galloway Forest, Dumfries and Galloway, Scotland, UK

Corvus corax

[edit] Identification

Large corvid, roughly 22-27 inches long. Wingspan reaches over 4 feet.
All-black with a purplish iridescence to its feathers. A powerful, thick "Roman Nose" beak is distinctive.

[edit] Similar Species

Photo by bobsofpa
Yellowstone National Park, Wyoming, USA, September 2006

This bird can be difficult to seperate from crows. Best told from its smaller cousins by its larger size and wedge-shaped (as opposed to fan-shaped) tail. Shaggier appearance overall, with long hackles on the throat and a shaggy crown. Bill is thicker and more powerful then that of a crow. Wingspan is longer, wings broader than crows, with more emarginated primaries (fingers). Much more prone to soaring than crows, wingbeats and flight more like that of a buzzard.

Best told from look-alike Chihuahuan Raven of the American Southwest by range, habitat, larger size, and, most reliably, the gray bases to the feathers on its neck (usually not visible except in windy conditions or when the bird is preening).

[edit] Distribution

Found across Eurasia and North America where it is expanding its range south. Range also extends into northern Africa.

Photo by john-henry
Camborne, Cornwall, February 2009

[edit] Taxonomy

[edit] Subspecies

This is a polytypic species, consisting of eight subspecies¹:

• C. c. corax - Europe and Mediterranean islands to western Asia
• C. c. kamtschaticus - Siberia to Sea of Okhotsk, Sakhalin, Kuril Islands and n Japan
• C. c. principalis - Islands in Bering Sea, Alaska, Canada and northern US
• C. c. sinuatus - W-central US to s Baja, Revillagigedo Islands and nw Nicaragua
• C. c. subcorax - SE Europe and Asia Minor to Pakistan and nw India
• C. c. tibetanus - Mountains of central Asia and the Himalayas
• C. c. tingitanus - Canary Islands and Coastal Morocco to Egypt.
• C. c. varius - Iceland and Faroe Islands

Genetic studies have shown quite deep divisions within the North American birds³.

[edit] Habitat

Very adaptable, able to survive in a wide range of habitats, from mountains to deserts to forests, though usually at higher elevations. Prefers wilderness regions, but slowly becoming conditioned to surviving alongside humans, in some cases even suburban areas. Increasing seen in urban areas.

[edit] Behaviour

Very intelligent, considered by many to be the most intelligent of all birds. Recent tests indicate that ravens may actually use a form of logic, not just trial-and-error or instinct, that begins as a basic framework of concepts and is added upon and improved with age and experience, just like with humans.

[edit] Flight

Soars often, and with all the prowess and aerial finesse of a raptor.

Quite playful, often observed exhibiting aerial maneuvers (generally in pairs) ranging from barrel rolls to dives. Even observed flying upside-down, sometimes for significant distances.

[edit] Diet

Omnivorous, consuming a wide range of food items. These include carrion (its usual fare) and vegetable matter (such as berries and nuts), as well as small animals that may be directly captured, occasionally up to the size of young squirrels. Ravens were once known as "wolf birds", due to their tendency to follow large mammal carnivores in hopes of scavenging the remains of their kills.

[edit] Breeding

They mate for life. A stick nest is built on a cliff ledge or in trees.

[edit] Vocalisation

Calls highly variable, but mainly croaking, resonating "Ka-ark!" or "Kronk!", as well as bell-like calls. Most vocalizations are lower and hoarser than those of crows.

[edit] In Culture

Ravens have long been viewed as mysterious and shadowy, likely due to their ebony plumage. Raven is one of the principle spirits in Native American Folklore. Though often portrayed as trickster, Raven is regarded by some tribes as the "Creator", the spirit who formed the earth. Ravens are often prominent figures on totem poles of Northwestern tribes.

Well-known is the superstition from King Charles II's time that, with the absence of ravens at the Tower of London, the tower and the kingdom would fall. Today, several ravens are permanently kept on the grounds, and tended to by "the Ravenmaster"⁴.

Ravens are popular in literature, often to set a dreary or ominous mood. Ravens were one of the birds most frequently mentioned in the works of William Shakespeare, and who could forget the corvid's appearance in Edgar Allen Poe's great poem, "The Raven"

[edit] References

1. Clements, JF. 2011. The Clements Checklist of Birds of the World. 6th ed., with updates to August 2011. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at http://www.birds.cornell.edu/clementschecklist/downloadable-clements-checklist
2. Collins Bird Guide ISBN 0 00 219728 6
3. Paper describing genetic findings with this species
4. [1]Wikipedia, "Ravens of the Tower of London", accessed 2012 December 2.

• List of references

[edit] External Links