These birds are slender with short, broad, rounded wings and a long tail which helps them maneuver in flight. They have long legs and long, sharp talons used to kill their prey, and a sharp, hooked bill used in feeding. Females tend to be larger than males. They often ambush their prey, mainly small birds and mammals, capturing them after a short chase. The typical flight pattern is a series of flaps followed by a short glide. They are commonly found in wooded or shrubby areas.
The procoracoid foramen (or coracoid foramen, coracoid fenestra) is a hole through the process at the front of the coracoid bone, which accommodates the supracoracoideus nerve. In some groups of birds it may be present as a notch, or incisura; or the notch may be partially or weakly closed with bone. In other groups the feature is completely absent.
The foramen is generally present in birds of prey, but it is absent in most Accipiter hawks that have been studied. This absence is proposed as a diagnostic feature.
A study of accipitrid skeletons found procoracoid incisurae (as opposed to foramina) in some specimens of the eagles Aquila gurneyi and A. chrysaetos, but not in four other Aquila species. The notch was variably open or weakly ossified in Spizastur melanoleucos, Lophoaetus occipitalis, Spizaetus ornatus, and Stephanoaetus coronatus. Also the buteonine hawks Buteo brachyurus and B. hemilasius had incisurae, differing from 17 other Buteo species.[5]
In Circus the foramen was found to be variable, not only within species but even between sides in the same individual. It is usually open or absent but may be closed by "a thread of bone". Research in genetic phylogeny has since indicated that Circus is closely related to Accipiter.
The notch was also absent or indistinct in Harpagus bidentatus.
Urotriorchis macrourus has a well-developed procoracoid foramen, which suggests a separation from Accipiter. It may be related to the chanting goshawks in tribe Melieraxini.[6]
Taxonomy
The genus Accipiter formerly contained around 50 species. A series of molecular phylogenetic studies found that the traditional arrangement was non-monophyletic. The publication of a densely sampled study of the Accipitridae in 2024 allowed the generic boundaries to be redefined.[7][8] To create monophyletic genera, species were moved from Accipiter to five new or resurrected genera leaving only 9 species in Accipiter. The southeast Asian crested goshawk and the Sulawesi goshawk were found to be only distantly related to other species in Accipiter. They were moved to a resurrected genus Lophospiza, the only genus placed in the new subfamily Lophospizinae. Similarly, the very small south America tiny hawk and semicollared hawk were found to be only distantly related to species in Accipiter. They were moved to a newly erected genus Microspizias which together with Harpagus is placed in the subfamily Harpaginae. The genera Circus, Megatriorchis, and Erythrotriorchis were found to be nested within Accipiter. Rather than subsuming these genera into an expanded Accipiter, species were moved from Accipiter to the resurrected genera Aerospiza, Tachyspiza and Astur.[9]
Angola, Democratic Republic of the Congo, Eritrea, Eswatini, Ethiopia, Kenya, Lesotho, Malawi, Mozambique, Rwanda, South Africa, South Sudan, Tanzania, Uganda, Zambia, and Zimbabwe.
eastern Colombia, southern Venezuela, the two Guyanas, Suriname, eastern Ecuador, central and eastern Peru, Amazonian Brazil, northern Bolivia, eastern Paraguay and northeast Argentina
^"Accipitridae". aviansystematics.org. The Trust for Avian Systematics. Retrieved 2023-07-26.
^Brisson, Mathurin Jacques (1760). Ornithologie; ou, Méthode contenant la division des oiseaux en ordres, sections, genres, espéces & leurs variétés (in French). Vol. 1. Paris: Jean-Baptiste Bauche. pp. 28, 310.
^Mindell, D.; Fuchs, J.; Johnson, J. (2018). "Phylogeny, taxonomy, and geographic diversity of diurnal raptors: Falconiformes, Accipitriformes, and Cathartiformes". In Sarasola, J.H.; Grange, J.M.; Negro, J.J. (eds.). Birds of Prey: Biology and conservation in the XXI century. Cham, Switzerland: Springer. pp. 3–32. ISBN978-3-319-73744-7.
^Catanach, T.A.; Halley, M.R.; Pirro, S. (2024). "Enigmas no longer: using ultraconserved elements to place several unusual hawk taxa and address the non-monophyly of the genus Accipiter (Accipitriformes: Accipitridae)". Biological Journal of the Linnean Society: blae028. doi:10.1093/biolinnean/blae028.
Balete, Danilo S.; Tabaranza, Blas R. Jr. & Heaney, Lawrence R. (2006): An Annotated Checklist of the Birds of Camiguin Island, Philippines. Fieldiana Zool. New Series106: 58–72. DOI:10.3158/0015-0754(2006)106[58:AACOTB]2.0.CO;2 HTML abstract
Heaney, Lawrence R. & Tabaranza, Blas R. Jr. (2006): Mammal and Land Bird Studies on Camiguin Island, Philippines: Background and Conservation Priorities. Fieldiana Zool. New Series106: 1–13. DOI:10.3158/0015-0754(2006)106[1:MALBSO]2.0.CO;2 HTML abstract