Family Hawks, Eagles (Accipitridae)


Grey-backed Hawk (Pseudastur occidentalis)


French: Buse à dos gris German: Graurückenbussard Spanish: Busardo dorsigrís

Leucopternis occidentalis


, 1876,

western Ecuador


Traditionally considered to form a species-group with P. albicollis and P. polionotus, and all sometimes considered conspecific. Recent molecular study supported relatively close relationship among these three (with albicollis and occidentalis as sister-species)#R; another study, however, found that nominate albicollis grouped with P. polionotus, and present species nestled within a clade containing all other taxa traditionally viewed as subspecies of P. albicollis#R. Monotypic.


W Ecuador (quite local, from S Esmeraldas to W Loja#R) and adjacent NW Peru (Tumbes). Single record from E Andean slope now questioned by its authors.

Descriptive notes

45–52 cm; one female 660 g; wingspan 104–116 cm. Adult is blackish-grey above, head grey, nape and mantle streaked with white; mid-length wings; short tail white... read more


In aerial display by pair, one bird dives almost vertically for up to several hundred metres while... read more


Tropical and subtropical semi-deciduous and evergreen forests, including drier Eriotheca (... read more

Food and feeding

Relatively few records available. Diet consists of lizards, snakes, crabs, small rodents, small birds, earthworms, frogs and large insects... read more


Previous observations of display activity and birds with nesting material indicated breeding in rainy season (Dec–Apr, especially Feb... read more



Status and conservation

ENDANGERED. CITES II. Very small population, in rapid decline owing to continuing habitat destruction. Confined to W Ecuador (Esmeraldas, Manabí, Pichincha, Los R... read more

Recommended citation

Bierregaard, R.O., Jr, Kirwan, G.M., Christie, D.A. & Boesman, P. (2019). Grey-backed Hawk (Pseudastur occidentalis). 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 on 25 May 2019).