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Mariana Crow - BirdForum Opus

Alternative names: Guam Crow; Kubary's Crow

Corvus kubaryi

Identification

38cm. A small crow, all black with a bluish gloss to rather "hair-like" plumage. Slim, deep based bill with an evenly, gently curving culmen and rather noticeable gonydeal angle. Flattish crown with a small, but steep forehead, short, blunt wingtips and long tail. Nasal plumes almost non-existant ( observable only in very close views )

Voice :- Fairly quite but gives a dual note 'scream' in flight and a quiet " chuckling" note when birds meet.

Distribution

Endemic to the Islands of Guam and Rota in the Northern Marianas Islands.
This species is critically endangered with an estimated global population of less than 250 birds, almost all of them on Rota. The arrival of the exotic brown tree-snake led to a massive decline of the population and the extinction of this crow on Guam in 2003. 10 birds were later translocated from Rota to Guam but only 4 survived until 2009.

Taxonomy

This is a monotypic species.
May have derived from House Crow.

Habitat

Mature forests, coastal strand vegetations, nests only in native limestone forest.

Behaviour

Diet includes insects, lizards, other birds' eggs, hermit crabs, fruits, and seeds.
Usually seen in pairs or small groups of up to 5 birds. Occasionally in bigger flocks.
Breeding mainly from August to February but may breed throughout the year. It builds a large, cupped platform of small sticks, lined with leaf fibres. 1-4 eggs are laid, and both parents incubate the eggs, brood the chicks, and care for the juveniles even after they fledge.
A resident species.

References

  1. Clements, JF. 2008. The Clements Checklist of Birds of the World. 6th ed., with updates to December 2008. Ithaca: Cornell Univ. Press. ISBN 978-0801445019.
  2. Del Hoyo, J, A Elliott, and D Christie, eds. 2009. Handbook of the Birds of the World. Volume 14: Bush-shrikes to Old World Sparrows. Barcelona: Lynx Edicions. ISBN 978-8496553507

Recommended Citation

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