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Roadside Hawk (Rupornis magnirostris)

Source: Wikipedia

Roadside hawk
In Goiás, Brazil
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Subfamily: Buteoninae
Genus: Rupornis
Kaup, 1844
Species:
R. magnirostris
Binomial name
Rupornis magnirostris
(Gmelin, JF, 1788)
Synonyms

Buteo magnirostris

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.[2]

Taxonomy

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The roadside hawk was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with the eagles, hawks and relatives in the genus Falco and coined the binomial name Falco magnirostris.[3] Gmelin based his description on the "Épervier à gros bec de Cayenne" that had been described and illustrated in 1770 by the French polymath Comte de Buffon in his multi-volume Histoire Naturelle des Oiseaux .[4][5] The roadside hawk is now the only species placed in the genus Rupornis that was introduced in 1844 by the German naturalist Johann Jakob Kaup.[6][7] The genus name combines the Ancient Greek rhupos meaning "dirt" or "filth" with ornis meaning "bird". The specific epithet magnirostris combines the Latin magnus meaning "great" with -rostris meaning "billed".[8]

Twelve subspecies are recognised. Their distributions are as follow:[7][9]

Description

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Immature, the Pantanal, Brazil

The roadside hawk is 31–41 cm (12–16 in) long and weighs 250–300 g (8.8–10.6 oz).[10] Males are about 20% smaller than females, but otherwise the sexes are similar.[11] 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.[12] 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, its beak is relatively large.[11]

The roadside hawk is the smallest hawk in the widespread genus Buteo;[13] although Ridgway's hawk and the white-rumped hawk are scarcely larger.[11] In flight, the relatively long tail and disproportionately short wings of the roadside hawk are distinctive. It frequently soars, but does not hover.[11]

Distribution and habitat

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In Palo Verde NP, Costa Rica

The roadside hawk is common throughout its range: from Mexico through Central America to most of South America east of the Andes Cordillera. Vagrants are occasionally found in Texas in the United States. 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.[14][15]

Behavior and ecology

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R. m. griseocauda eating speckled racer, Belize

Breeding

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The bulky stick nest is lined with leaves and placed near the top of a tree. The clutch of one or two eggs is incubated for around 37 days, beginning after the first egg is laid.[16]

Food and feeding

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Defecating

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.[17] 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.[18]

Hunting

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Roadside hawks regularly hunt using the "still hunting" method while patiently waiting for prey. While perch hunting, a hawk will drop or glide down from an elevated position to capture their prey.[19] Though most attempts are successful through this technique, it is crucial to consider that their style of hunting varies in success depending on the habitat they explore.[20]

References

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  1. ^ BirdLife International (2020). "Rupornis magnirostris". IUCN Red List of Threatened Species. 2020: e.T22695880A168800737. doi:10.2305/IUCN.UK.2020-3.RLTS.T22695880A168800737.en. Retrieved 12 November 2021.
  2. ^ South American Classification Committee (2011) Revise generic boundaries in the Buteo group. Accessed 16 June 2011
  3. ^ Gmelin, Johann Friedrich (1788). Systema naturae per regna tria naturae : secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Vol. 1, Part 1 (13th ed.). Lipsiae [Leipzig]: Georg. Emanuel. Beer. p. 282.
  4. ^ Buffon, Georges-Louis Leclerc de (1770). Histoire Naturelle des Oiseaux (in French). Vol. 1. Paris: De l'Imprimerie Royale. pp. 237–238.
  5. ^ Buffon, Georges-Louis Leclerc de; Martinet, François-Nicolas; Daubenton, Edme-Louis; Daubenton, Louis-Jean-Marie (1765–1783). Planches Enluminées D'Histoire Naturelle. Vol. 5. Paris: De L'Imprimerie Royale. Plate 464.
  6. ^ Kaup, Johann Jakob (1844). Classification der Säugethiere und Vögel (in German). Darmstadt: Carl Wilhelm Leske. p. 120. Retrieved 28 December 2022 – via Biodiversity Heritage Library.
  7. ^ a b Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (2023). "Hoatzin, New World vultures, Secretarybird, raptors". IOC World Bird List. 13.2. International Ornithologists' Union. Retrieved 22 December 2023.
  8. ^ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p. 343, 237. ISBN 978-1-4081-2501-4.
  9. ^ Clement, J.F. (2007). The Clements Checklist of the Birds of the World (6th ed.). Christopher Helm. ISBN 978-0-7136-8695-1.
  10. ^ "Roadside Hawk". oiseaux-birds.
  11. ^ a b c d Ferguson-Lees, James; Christie, David A. (2001). Raptors of the World. London: Christopher Helm. ISBN 0-7136-8026-1.
  12. ^ 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.
  13. ^ Bierregaard, Richard O.; Boesman, Peter F.D.; Kirwan, Guy M. (4 March 2020). "Roadside Hawk Rupornis magnirostris". Birds of the World. Cornell Lab of Ornithology. Retrieved 15 September 2022.
  14. ^ BirdLife species factsheet for Buteo magnirostris
  15. ^ 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.
  16. ^ Thiollay, J.M. (1994). "Roadside hawk". In del Hoyo, J.; Elliott, A.; Sargatal, J. (eds.). Handbook of the Birds of the World. Vol. 2: New World Vultures to Guineafowl. Barcelona, Spain: Lynx Edicions. p. 179. ISBN 978-84-87334-15-3.
  17. ^ 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). 24 (3): 709–716. doi:10.1590/S0101-81752007000300022.
  18. ^ Ragusa-Netto, J. (2000). "Raptors and 'campo-cerrado' bird mixed flock led by Cypsnagra hirundinacea (Emberizidae: Thraupinae)". Revista Brasileira de Biologia. 60 (3): 461–467. doi:10.1590/S0034-71082000000300011. hdl:11449/28947. PMID 11188872.
  19. ^ Whitacre, David (2013). Neotropical Birds of Prey: Biology and Ecology of a Forest Raptor Community. Cornell University Press. ISBN 978-0-8014-6611-3.[page needed]
  20. ^ Panasci, Theresa; Whitacre, David (2000). "Diet and Foraging Behavior of Nesting Roadside Hawks in Petén, Guatemala". The Wilson Bulletin. 112 (4): 555–558. doi:10.1676/0043-5643(2000)112[0555:DAFBON]2.0.CO;2. JSTOR 4164283.
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