Pied crow

The pied crow (Corvus albus) is a widely distributed African bird species in the crow genus.

Pied crow
In Etosha National Park, Namibia
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Corvidae
Genus: Corvus
Species:
C. albus
Binomial name
Corvus albus

Structurally, the pied crow is better thought of as a small crow-sized raven, especially as it can hybridise with the Somali crow (dwarf raven) where their ranges meet in the Horn of Africa. Its behaviour, though, is more typical of the Eurasian carrion crows, and it may be a modern link (along with the Somali crow) between the Eurasian crows and the common raven.

Description

It is approximately the size of the European carrion crow or a little larger (46–50 cm in length) but has a proportionately larger bill, slightly longer tail and wings, and longer legs. As its name suggests, its glossy black head and neck are interrupted by a large area of white feathering from the shoulders down to the lower breast. The tail, bill and wings are black too. The eyes are dark brown. The white plumage of immature birds is often mixed with black. It resembles the white-necked and thick-billed ravens but has a much smaller bill.[2]

Measurements
  • Length 46 – 52 cm[3]
  • Wing 328 to 388 mm (17 unsexed birds)[3]
  • Weight 520g[3]

Identification

In southern Africa the range overlaps with the white-necked raven. The pied crow is slightly smaller and has a white chest and belly with a black, more delicate beak compared to the black chest and belly of the larger white-necked raven which also has a white tipped and weightier beak.[4] It is larger than the black crow.

Voice

The voice is described as a harsh "ar-ar-ar-ar" or "karh-karh-karh".[5]

Taxonomy

The pied crow was first described in 1776 by Statius Muller. Its specific name is the Latin adjective albus, meaning "white".

The Maasai people call it Ol-korrok from the sound of its call. It is considered annoying but not a bird of ill-omen.[6]

Distribution and habitat

This species, Africa's most widespread member of the genus Corvus, occurs from Sub-Saharan Africa, specifically Nigeria, Ghana,Senegal, Sudan, Somalia Eritrea, Zambia and Zimbabwe down to the Cape of Good Hope and on the large island of Madagascar, the Comoros islands, Aldabra, Assumption Island, Cosmoledo, Astove Island, Zanzibar, Pemba and Fernando Po. It inhabits mainly open country with villages and towns nearby. It does not occur in the equatorial rainforest region. It is rarely seen very far from human habitation, though it is not as tied to the urban way of life as the house crow (Corvus splendens) of Asia, and may be encountered far from human habitation in Eritrea.[2]

Behaviour
In flight

Pied crows are generally encountered in pairs or small groups, although an abundant source of food may bring large numbers of birds. The species behaves in a similar manner to the hooded and carrion crows.[7] In Dakar, birds have been observed mobbing passing ospreys and snake eagles but avoiding black kites.

Diet

All of its food is obtained from the ground, trees, etc. including injured wildlife such as insects and other small invertebrates, small reptiles, small mammals, young birds and eggs, grain, peanuts, carrion and any scraps of human food and fruit.[8] It has been recorded killing and eating roosting Fruit Bats and is frequently seen (sometimes in huge numbers) scavenging around slaughterhouses.

Reproduction

The nest is usually built in tall, isolated trees, though sometimes smaller specimens are used, depending on availability. The cross supports of telephone poles are also frequently used, and both sexes build the nest. A clutch of 3–6 eggs is laid from September to November (depending on latitude) and are pale green spotted with various shades of brown. The eggs are normally covered when the incubating female leaves the nest. Incubation is 18–19 days and the young are usually fledged by around 45 days. Both sexes rear the young.[7]

See also

References
  1. BirdLife International (2013). "Corvus albus". IUCN Red List of Threatened Species. 2013. Retrieved 26 November 2013.CS1 maint: uses authors parameter (link) CS1 maint: ref=harv (link)
  2. Goodwin, p. 132
  3. Roberts' Birds of Southern Africa. The John Voelker Bird Book Fund. p. 474. ISBN 0-620-17583-4.
  4. Roberts' Birds of Southern Africa. The John Voelker Bird Book Fund. pp. 474–477. ISBN 0-620-17583-4.
  5. Goodwin, p. 134
  6. Galaty, John G. (1998). "The Maasai Ornithorium: Tropic Flights of Avian Imagination in Africa". Ethnology. 37 (3): 227–238. doi:10.2307/3774014.
  7. Goodwin, p. 133
  8. Goodwin, pp. 132-33

Cited text
  • Goodwin D. (1983). Crows of the World. Queensland University Press, St Lucia, Qld. ISBN 0-7022-1015-3.
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