Buteo (Etymology: Buteo is the Latin name of the Common Buzzard) is a genus of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "buzzards", but "hawk" is used in North America. As both terms are ambiguous, buteo is sometimes used instead, for example, by the Peregrine Fund.^[1]

Characteristics

Buteos range in size from the Roadside Hawk, which averages 270 grams (9.5 oz) and 35 cm (14 in) long, to the Ferruginous Hawk and Upland Buzzard, both at 1,350 grams (3 lbs) and 60 cm (24 in) long. They are noted for their broad wings and sturdy builds. The Buteos frequently soar on thermals at mid-day over openings and are most frequently seen while doing this. They inhabit a wide range of habitats across the world but tend to prefer some access to both clearings and trees.

All Buteo species are to some extent opportunistic when it comes to hunting, and will prey on almost any type of small animal as it becomes available to them. However, most have a strong preference for small mammals and among these mostly rodents. Rodents of almost every family in the world are somewhere predated by Buteo species. Birds are taken occasionally, as well, although most small birds can successfully evade them. Mid-sized birds, such as waterfowl, corvids, pigeons and gamebirds, are most often taken, but even these are generally taken when distracted. Other prey may include snakes, lizards, frogs, salamanders, fish, and even various invertebrates, especially beetles. Carrion is eaten occasionally by most species, but is almost always secondary to live prey. Prey is often spotted from a great distance while soaring and is set down upon while circling down to the ground. Other Buteo species may prefer to ambush prey by pouncing down to the ground directly from a perch.

The Buteo hawks include many of the most widely distributed and best-known raptors in the world. Examples include the Red-tailed Hawk of North America, the Common Buzzard of Eurasia, and the Roadside Hawk of tropical Central and South America. Most Northern Hemisphere species are at least partially migratory. In North America, species such as Broad-winged Hawks and Swainson's Hawks are known for their huge numbers (often called "kettles") while passing over major migratory flyways in the fall.

Species in taxonomic order

The Grey-lined Hawk (Buteo nitidus) has distinct coloration but otherwise is a normal buteo.

Ferruginous Hawk (Buteo regalis)

• Common Buzzard, Buteo buteo
  • Eastern Buzzard, Buteo buteo japonicus
  • Himalayan Buzzard, Buteo buteo burmanicus
  • Madeira Buzzard, Buteo buteo harterti
  • Steppe Buzzard, Buteo buteo vulpinus
• Cape Verde Buzzard, Buteo bannermani
• Socotra Buzzard, Buteo socotraensis
• Red-tailed Hawk, Buteo jamaicensis
• Long-legged Buzzard, Buteo rufinus
• Rough-legged Buzzard, Buteo lagopus
• Ferruginous Hawk, Buteo regalis
• Red-shouldered Hawk, Buteo lineatus
• Broad-winged Hawk, Buteo platypterus
• Swainson's Hawk, Buteo swainsoni
• Roadside Hawk, Buteo magnirostris
• Ridgway's Hawk, Buteo ridgwayi
• White-rumped Hawk, Buteo leucorrhous
• Short-tailed Hawk, Buteo brachyurus
• White-throated Hawk, Buteo albigula
• White-tailed Hawk, Buteo albicaudatus
• Galápagos Hawk, Buteo galapagoensis
• Variable Hawk, Buteo polyosoma
  • Red-backed Hawk, Buteo (p.) polyosoma
  • Juan Fernández Hawk, Buteo (polyosoma) exsul
  • Puna Hawk, Buteo (polyosoma) poecilochrous
• Grey Hawk, Buteo nitidus - formerly in Asturina
  • Grey-lined Hawk, Buteo n. nitidus
  • Grey Hawk, Buteo nitidus plagiatus
• Zone-tailed Hawk, Buteo albonotatus
• Hawaiian Hawk, Buteo solitarius
• Rufous-tailed Hawk, Buteo ventralis
• Mountain Buzzard, Buteo oreophilus
  • Forest Buzzard, Buteo oreophilus trizonatus
• Madagascar Buzzard, Buteo brachypterus
• Upland Buzzard, Buteo hemilasius
• Red-necked Buzzard, Buteo auguralis
• Jackal Buzzard, Buteo rufofuscus
• Archer's Buzzard, Buteo archeri
• Augur Buzzard, Buteo augur

Fossil record^[2]

A number of fossil species have been discovered, mainly in North America. Some are placed here primarily based on considerations of biogeography, Buteo being somewhat hard to distinguish from Geranoaetus based on osteology alone:^[3]

• Buteo fluviaticus (Brule Middle Oligocene of Wealt County, USA) - possibly same as B. grangeri
• Buteo grangeri (Brule Middle Oligocene of Washabaugh County, USA)
• Buteo antecursor (Brule Late Oligocene)
• ?Buteo sp. (Brule Late Oligocene of Washington County, USA)^[4]
• Buteo ales (Agate Fossil Beds Early Miocene of Sioux County, USA) - formerly in Geranospiza or Geranoaetus
• Buteo typhoius (Olcott Early ?- Snake Creek Late Miocene of Sioux County, USA)
• Buteo pusillus (Middle Miocene of Grive-Saint-Alban, France)
• Buteo sp. (Middle Miocene of Grive-Saint-Alban, France - Early Pleistocene of Bacton, England)^[5]
• Buteo contortus (Snake Creek Late Miocene of Sioux County, USA) - formerly in Geranoaetus
• Buteo spassovi (Late Miocene of Chadžidimovo, Bulgaria)
• Buteo musculosus (Miocene of Argentina) - formerly in Thegornis
• Buteo conterminus (Snake Creek Late Miocene/Early Pliocene of Sioux County, USA) - formerly in Geranoaetus
• Buteo sp. (Late Miocene/Early Pliocene of Lee Creek Mine, USA)
• Buteo sanya (Late Pleistocene of Luobidang Cave, China)

An unidentifiable accipitrid that occurred on Ibiza in the Late Pliocene/Early Pleistocene may also have been a Buteo.^[6] If this is so, the bird can be expected to aid in untangling the complicated evolutionary history of the Common Buzzard group.

The prehistoric species "Aquila" danana, Buteogallus fragilis (Fragile Eagle), and Spizaetus grinnelli were at one time also placed in Buteo.^[3]

Footnotes

References

Wikimedia Commons has media related to: Buteo

• "Raptors of the World" by Ferguson-Lees, Christie, Franklin, Mead & Burton. Houghton Mifflin (2001), ISBN 0-618-12762-3.
• Alcover, Josep Antoni (1989): Les Aus fòssils de la Cova de Ca Na Reia. Endins 14-15: 95-100. [In Catalan with English abstract]
• Ballmann, Peter (1969): Les Oiseaux miocènes de la Grive-Saint-Alban (Isère) [The Miocene birds of Grive-Saint-Alban (Isère)]. Geobios 2: 157-204. [French with English abstract] doi:10.1016/S0016-6995(69)80005-7 (HTML abstract)
• Brodkorb, Pierce (1964): Catalogue of Fossil Birds: Part 2 (Anseriformes through Galliformes). Bulletin of the Florida State Museum 8(3): 195-335. PDF or JPEG fulltext
• Cracraft, Joel (1969): Notes on fossil hawks (Accipitridae). Auk 86(2): 353-354. PDF fulltext
• Mlíkovský, Jirí (2002): Cenozoic Birds of the World, Part 1: Europe. Ninox Press, Prague. ISBN 80-901105-3-8 PDF fulltext
• Wetmore, Alexander (1933): Status of the Genus Geranoaëtus. Auk 50(2): 212. DjVu fulltext PDF fulltext