Family Crows and Jays (Corvidae)

Least Concern

Common Raven (Corvus corax)


Taxonomy

French: Grand Corbeau German: Kolkrabe Spanish: Cuervo grande
Other common names: Northern Raven
Taxonomy:

Corvus Corax

Linnaeus

, 1758,

Sweden

.

Recent genetic investigations#R suggest species consists of at least three groups that are currently taking relatively independent evolutionary paths. Little, if any, genetic exchange occurs between Old World and New World populations, allowing these two groups to maintain slight, but distinctive genetic signatures, in addition to which those in Canary Is (samples from Fuerteventura I only) are morphologically and genetically distinct from other Old World ravens (apparently having diverged c. 650,000 years ago). Thus, populations in Canary Is, those elsewhere in Old World, and those in New World appear sufficiently isolated today to be evolving independently. In Old World, a variety of described morphological forms may have been especially distinct 1 million years ago, but today they intergrade extensively and do not have unique mitochrondrial signatures. Similar process appears to be reducing genetic diversity in New World, where two clades recognized in current mtDNA samples: “California clade” found throughout W USA and represents most individuals in Mojave Desert, and “Holarctic clade” (occurs also throughout Old World) identified from samples in N North America (Alaska, Canada, Maine and Greenland); ravens from the two clades co-exist in roughly equal proportions in large area of North America (including Washington and Idaho), and where mating patterns and clade identity known (temperate rainforests of Olympic Peninsula, in Washington State) intercladal pairing is common, suggesting substantial gene flow between clades and a shared current evolutionary trajectory. Existence of both clades in W North America suggests that ravens may have colonized North America at least twice. Initially, “California clade” and “Holarctic clade” diverged from each other c. 2 million years ago, perhaps as glacial advances pushed original population into S refugia, and these distinct “California clade” ravens remained isolated from other (“Holarctic clade”) ravens for c. 1 million years; during this time their sister-taxon, C. cryptoleucus, evolved, these taxa differing by 1.75% to 1.8% (suggesting that they diverged 1.1–0.6 million years ago, well after the two clades of present species diverged). “Holarctic clade” may have reinvaded North America across Bering Strait in last 15,000 years in company of humans and grey wolves (Canis lupus). Many races described on basis of clines in morphology (decrease in size from N and high-elevation portions of range to S and desert parts) and plumage (decrease in bluish gloss and less pronounced lanceolate throat plumes from N to S); nominate race grades into laurencei in C Europe, and into kamtschaticus in W Siberia and W Russia and S to Black Sea, Caucasus, N Iran and Kazakhstan. Twelve subspecies currently recognized.

Subspecies and Distribution
  • C. c. principalis Ridgway, 1887 – Alaska E across ice-free portions of Canada to coasts of Greenland, S in USA to Pacific coast of Oregon and Washington and, in E, in Appalachian Mts S to N Georgia.
  • C. c. sinuatus Wagler, 1829 – Rocky Mts from SW Canada (British Columbia) S in E USA through Idaho, Montana, Utah and Colorado and through Great Plains, Great Basin and SW mountains, to mainland Mexico and Nicaragua.
  • C. c. clarionensis Rothschild & E. J. O. Hartert, 1902 – SW USA (N California) S through NW Mexico (Baja California, including Clarion I) and E through Mojave Desert.
  • C. c. varius Brünnich, 1764 – Iceland and Faroe Is.
  • C. c. corax Linnaeus, 1758 – NW Europe from British Is and Fennoscandia S through W & C Europe, Caucasus, NE Turkey, N Iran and E to N Kazakhstan and C Siberia (R Yenisey).
  • C. c. kamtschaticus Dybowski, 1883 – Siberia E to Kamchatka, Commander Is and coastal regions of Sea of Okhotsk, S to N Mongolia, NE China, Sakhalin, Kurils and N Japan (Hokkaido).
  • C. c. hispanus E. J. O. Hartert & O. Kleinschmidt, 1901 – Iberian Peninsula, Balearic Is, Corsica, Sardinia and Italy.
  • C. c. laurencei A. O. Hume, 1873 – E Greece and Cyprus E through Middle East to E Kazakhstan, W China (except mountains) and NW India.
  • C. c. tibetanus Hodgson, 1849 – C Asia from Tien Shan and Pamirs S to Himalayas and W China mountains.
  • C. c. canariensis E. J. O. Hartert & O. Kleinschmidt, 1901 – W Canary Is.
  • C. c. jordansi Niethammer, 1953 – E Canary Is (Lanzarote, Fuerteventura)#R.
  • C. c. tingitanus Irby, 1874 – coastal regions of N Africa from Morocco (S to pre-Saharian Atlas) E to Egypt.
  • Descriptive notes

    58–69 cm; 585–2000 g; wingspan 120–150 cm. The largest corvid; large, powerful bill with nasal bristles covering half or less of exposed culmen, throat feathers... read more

    Voice

    Large repertoire of at least 20 distinct calls of known function, 79 call types distinguished... read more

    Habitat

    Extreme habitat generalist, breeding throughout forested and open coastal, steppe, mountain, desert... read more

    Food and feeding

    Opportunistic scavenger, historically closely associated with large carnivores, most notably wolves, and wasteful omnivores, notably humans... read more

    Breeding

    Breeds early in the year when snow often blankets the ground. Laying from late Feb in most of range, earlier in some areas, e.g. Dec in far... read more

    Movements

    Relatively sedentary. Breeders may fly up to 30 km from nest to predictable food sources and travel... read more

    Status and conservation

    Not globally threatened. Common to locally abundant. Occurs in widely distributed, low-density, and self-sustaining populations across most of its range; variation on this... read more

    Recommended citation

    Marzluff, J. (2017). Common Raven (Corvus corax). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/60808 on 18 November 2017).