The roadside hawk (Rupornis magnirostris) is a relatively small bird of prey found in the Americas. This vocal species is often the most common raptor in its range. It has many subspecies and is now usually placed in the monotypic genus Rupornis instead of Buteo.
The roadside hawk is 31–41 cm (12–16 in) long and weighs 250–300 g (8.8–10.6 oz). Males are about 20% smaller than females, but otherwise the sexes are similar. In most subspecies, the lower breast and underparts are barred brown and white, and the tail has four or five grey bars. Twelve subspecies are usually recognised and there is significant plumage variation between these. Depending on the subspecies involved, the roadside hawk is mainly brown or grey. It is fairly common to observe a touch of rufous (i.e., a light reddish-brown) on the bird's wings, especially when seen in flight. Its call is a very high-pitched piercing squeak. The eyes of adult roadside hawks are whitish or yellow. As suggested by its specific name (magni = large; rostri = beak), its beak is relatively large.
The roadside hawk may be marginally the smallest hawk in the widespread genus Buteo, although Ridgway's hawk and the white-rumped hawk are scarcely larger. In flight, the relatively long tail and disproportionately short wings of the roadside hawk are distinctive. It frequently soars, but does not hover.
The subspecies and their distributions are:
- R. m. griseocauda – (Ridgway, 1874): found in Mexico (south from Colima, Nuevo León and Tamaulipas, except Yucatán and Tabasco) south to northwest Costa Rica and west Panama (Chiriquí).
- R. m. conspectus – Peters, 1913: found in southeast Mexico (Tabasco and Yucatán Peninsula) and north Belize.
- R. m. gracilis – Ridgway, 1885: found on Cozumel and Isla Holbox, near Yucatán (Mexico).
- R. m. sinushonduri – (Bond, 1936): found on Bonacca Island and Roatán, off Honduras.
- R. m. petulans – van Rossem, 1935: found in southwest Costa Rica and Pacific slope of west Panama to Tuira River, and adjacent islands.
- R. m. alius – Peters & Griscom, 1929: found on San José and San Miguel, in Pearl Islands (Gulf of Panama).
- R. m. magnirostris – (Gmelin, 1788): nominate, found in Colombia south to west Ecuador, east to Venezuela and the Guianas, and south to Amazonian Brazil (Madeira River east to Atlantic coast).
- R. m. occiduus – Bangs, 1911: found in east Peru, west Brazil (south of Amazon, west of Madeira River) and north Bolivia.
- R. m. saturatus – (P.L. Sclater & Salvin, 1876): found in Bolivia, through Paraguay and southwest Brazil (southwest Mato Grosso) to west Argentina (south to La Rioja).
- R. m. nattereri – (P.L. Sclater & Salvin, 1869): found in northeast Brazil south to Bahia.
- R. m. magniplumis – (Bertoni, 1901): found in south Brazil, north Argentina (Misiones) and adjacent Paraguay.
- R. m. pucherani – (J. Verreaux & E. Verreaux, 1855): found in Uruguay and northeast Argentina (south to Buenos Aires Province).
Range and habitat
The roadside hawk is common throughout its range: from Mexico through Central America to most of South America east of the Andes cordillera. It is found from the northern Caribbean coast of South America south to the northeastern parts of Argentina. With the possible exception of dense rainforests, the roadside hawk is well adapted to most ecosystems in its range. It is also an urban bird, and is possibly the most common species of hawk seen in various cities throughout its range—or perhaps just the most conspicuous one, as it becomes aggressive when nesting and has been recorded attacking humans passing near the nest.
Food and feeding
The roadside hawk's diet consists mainly of insects, squamates, and small mammals, such as young common marmosets and similar small monkeys which are hunted quite often. It will also take small birds, but far less often than generalists such as the related but larger white-tailed hawk, or bird specialists like the more distantly related aplomado falcon. Mixed-species feeding flocks it encounters when hunting in open cerrado habitat are not particularly wary of it: they watch it lest the hawk come too close, but consider them hardly more of a threat than the diminutive American kestrel.
- ^ BirdLife International (2012). "Buteo magnirostris". IUCN Red List of Threatened Species. Version 2012.1. International Union for Conservation of Nature. Retrieved 16 July 2012.
- ^ South American Classification Committee (2011) Revise generic boundaries in the Buteo group. Accessed 16 June 2011
- ^ "Roadside Hawk". oiseaux-birds.com.
- ^ a b c d Ferguson-Lees, James; Christie, David A. (2001). Raptors of the World. London: Christopher Helm. ISBN 0-7136-8026-1.
- ^ As illustrated in: Frisch, J.D.; Frisch, C.D. (2005). Aves Brasileiras e Plantas que as Atraem [Brazilian birds and plants attractive to them] (in Portuguese). São Paulo: Dalgas Ecotec. p. 191. ISBN 85-85015-07-1.
- ^ Clement, J.F. (2007). The Clements Checklist of the Birds of the World (6th ed.). ISBN 978-0-7136-8695-1.
- ^ BirdLife species factsheet for Buteo magnirostris
- ^ Pereira, José Felipe Monteiro (2008). Aves e Pássaros Comuns do Rio de Janeiro [Common birds of Rio de Janeiro] (in Portuguese). Rio de Janeiro: Technical Books Editora. p. 41. ISBN 978-85-61368-00-5.
- ^ de Lyra-Neves, Rachel M.; Oliveira, Maria A.B.; Telino-Júnior, Wallace R.; dos Santos, Ednilza M. (2007). "Comportamentos interespecíficos entre Callithrix jacchus (Linnaeus) (Primates, Callitrichidae) e algumas aves de Mata Atlântica, Pernambuco, Brasil" [Interspecific behaviour between Callithrix jacchus (Linnaeus) (Callitrichidae, Primates) and some birds of the Atlantic forest, Pernanbuco State, Brazil]. Revista Brasileira de Zoologia (in Portuguese with English abstract) 24 (3): 709–716. doi:10.1590/S0101-81752007000300022.
- ^ Ragusa-Netto, J. (2000). "Raptors and "campo-cerrado" bird mixed flock led by Cypsnagra hirundinacea (Emberizidae: Thraupinae)". Revista Brasileira de Biologia (in English with Portuguese abstract) 60 (3): 461–467. doi:10.1590/S0034-71082000000300011. PMID 11188872.