SPECIES

Red-tailed Hawk Buteo jamaicensis Scientific name definitions

C. R. Preston and R. D. Beane
Version: 1.0 — Published March 4, 2020
Text last updated May 20, 2009

Systematics

Systematics History

Editor's Note: This article requires further editing work to merge existing content into the appropriate Subspecies sections. Please bear with us while this update takes place.

Geographic Variation

Considerable but complicated variation across vast geographic range, making trends difficult to summarize. Various populations in West and in Middle America are polymorphic, but polymorphism is absent or rare in others. Tendency toward smaller size in West Indies, se. Alaska, and Middle America. Southern populations generally more richly colored ventrally. Breast band tends to weaken from north to south and from west to east. Some evidence of Gloger's rule, at least in eastern populations, with increasingly heavily marked birds in colder north (Wheeler 2003b:319).

Subspecies

Twelve subspecies in two groups: Harlan's Hawk (B. j. harlani), formerly treated as a distinct species (Peters 1931, American Ornithologists' Union 1957) -- and may yet prove to be given limited interbreeding with neighboring populations where ranges meet (W. S. Clark pers. comm.) -- and all other “typical” Red-tailed Hawks. Diagnoses below are for adults; see Wheeler (Wheeler 2003b) for details on separating younger birds in the United States and Friedmann (Friedmann 1950a) for separating other populations. Note that individual variation is extreme so, as with most subspecies, field identification to a particular subspecies may not be possible in many cases (see Liguori 2001).

Typical Red-tailed Hawks

B. j. borealis (Gmelin, 1788). Includes Falco leverianus Gmelin, 1788, F. aquilinus Barton, 1799, Accipiter ruficaudus Vieillot, 1807, B. ferruginicaudus Vieillot, 1807, B. gallinivorus Vieillot, 1816, B. americanus Vieillot, 1816, B. pictus Phillipi, 1899, B. j. kriderii Hoopes, 1873, and B. j. abieticola Todd, 1950. Breeds from sw. Alberta east to w. Hudson Bay, e. Québec, and Maritime Provinces and south from e. Texas east to n. Florida [type locality = South Carolina]; winters from n. Great Plains and s. New England south to e. Mexico; vagrant to Bermuda.

Polymorphic, with a “typical” light morph and a white morph (Taverner 1936b), the latter often called Krider's Hawk (see below); dark morph rare and perhaps absent (Palmer 1988f). Dorsum dark brown mottled with rufous or white; tail largely unmarked chestnut with narrow white tip and narrow black subterminal band; remiges dark gray, whitish basally; primaries black, tips barred; secondaries barred and mottled; throat typically white; ventrum white; belly band of fuscous streaks; flanks occasionally barred rufous; underwing white or tawny with distinct dark patagial bar; male wing > 337 mm, female wing > 370 mm. B. j. “kriderii” does not have a breeding range distinct from those of other subspecies, meaning it cannot, by definition, be a valid subspecies; instead, its breeding range occupies the sw. portion of that of B. j. borealis, and it winters chiefly in the Great Plains (Dickerman 1989a). This white morph is diagnosed by it tail being extensively white (with distal one-third reddish), white face, and pale underwing lacking or with a greatly faded patagial bar. Although B. j. abieticola was initially recognized by Dickerman and Parkes (Dickerman and Parkes 1987) and Dickerman (Dickerman 1989a), its heavy markings are not restricted to the boreal region of e. Canada from which Todd (Todd 1950) described it (Wheeler 2003b).

B. j. umbrinus Bangs, 1901. Includes B. j. solitudinus Barbour, Barbour 1935. Resident in peninsular Florida, the Bahamas, and Cuba, including Isle of Pines [type locality = Myakka, Manatee Co., Florida]. Monomorphic; like light morph B. j. borealis but rectrices with dark barring near shafts. Birds from Cuba are purportedly smaller (B. j. “solitudinus”) but otherwise do not differ. Wing chord values listed by Barbour (Barbour 1935) and Friedmann (Friedmann 1950a) suggest broad overlap with birds from Florida.

B. j. jamaicensis (Gmelin, 1788). Includes B. fulvus Vieillot, 1807, and B. tropicalis Verrill and Verrill, 1909. Resident in Jamaica, Hispaniola, Puerto Rico, and Virgin Is. [type locality = Jamaica]. Monomorphic; similar to light morph B. j. borealis but small (male wing < 340 mm; female wing < 371 mm), dorsum less mottled, belly band heavy and black, rectrices lack white tip, and thighs always barred rufous.

B. j. alascensis Grinnell, 1909. Breeds in se. Alaska from Yakutat to Ketchikan; resident from there south to sw. British Columbia, including Queen Charlotte Is. and Vancouver I. [type locality = Glacier Bay, Alaska]; vagrant to n. California (Bolinas, 30 December 2006; P. Pyle in litt.). Polymorphic (Taverner 1936b); like B. j. borealis but rectrices with narrow, wavy bars throughout and underwings rich tawny or pale rufous; size much smaller than in adjacent B. j. calurus populations—e.g., “largest females smaller than almost all males from elsewhere in Canada” (Palmer 1988f:105).

B. j. calurus Cassin, 1855. Includes B. montanus Gambel, 1846, B. j. lucansanus Coues, 1873, B. rufescentior Salvin and Godman, 1900, and B. j. socorroensis Ridgway, 1880. Breeds w. of Rocky Mts. from e. Alaska south to Arizona and New Mexico, with breeding range also extending eastward through n. Alberta to nw. Manitoba; resident from s. British Columbia and nw. Manitoba, southward; winters through s. Great Plains to w. Gulf of Mexico and south through Middle America [type locality = Ft. Webster, New Mexico]. Polymorphic, with distinct dark, rufous, and light morphs but also numerous intermediates along a continuum. Like B. j. borealis but belly band heavier, buffy or tawny ventrally (less white); only subspecies with barring (not streaking) forming belly band; throat typically dark brown. Polymorphic birds resident on Isla Socorro in Revillagigedo archipelago, sw. of tip of Baja California peninsula, were described as subspecifically distinct, but Jehl and Parkes (Jehl and Smith 1970) reported “that socorroensis cannot be separated from calurus on the basis of color and the validity of socorroensis must rest on its more robust legs and feet.” Although asserting that “The diameter of its tarsi and toes is obviously greater,” they further remarked that “this is not revealed by standard linear measurements” and recommended “comparative measurements should be made on osteological material, which is not available for the island form.” Without such data, the subspecies' validity cannot be established.

B. j. suttoni Dickerman, 1993. Resident in Sierra de la Laguna, Baja California Sur. Monomorphic; like light morph B. j. calurus but belly band weak (matching B. j. fuertesi) and barring on thigh paler; throat typically white; averages less mottled dorsally and perhaps consistently smaller than either B. j. calurus or B. j. fuertesi (Dickerman 1994).

B. j. fuertesi Sutton and Van Tyne, 1935. Resident from se. Arizona east to cen. Texas, south to Durango and east to Tamaulipas [type locality = 22 mi. s. of Alpine, Brewster Co., Texas]. Monomorphic; like B. j. suttoni but whiter (less rufescent) ventrally; size of B. j. calurus.

B. j. fumosus Nelson, 1898. Resident on Tres Marías Islands off Nayarit [type locality = Isla María Madre, Nayarit]. Monomorphic; like light morph B. j. calurus but duskier dorsally, thighs heavily barred, rustier ventrally; throat typically dark (Grant 1965a).

B. j. hadropus Storer, 1962. Resident from s. Durango and San Luis Potosí south to Isthmus of Tehuantepec [type locality = Chilpáncingo, Guerrero]. Polymorphic; like B. j. calurus but belly band formed by a mix of bars and streaks; in light morph, ventrum white (not buffy or tawny); averages smaller than B. j. calurus (Palmer 1988f).

B. j. kemsiesi Oberholser, 1959. Resident from Chiapas south to n. Nicaragua [type locality = Tegucigalpa, Honduras]. Polymorphic; like B. j. fuertesi but belly band absent or faint, flanks barred with pale rufous, paler overall, and averages smaller (size of B. j. hadropus).

B. j. costaricensis Ridgway, 1874. Resident in highlands of Costa Rica and w. Panamá [type locality = Costa Rica]. Monomorphic; like light morph B. j. jamaicensis but larger (size of B. j. hadropus), belly band dark rufous mottled with black, and thighs solid (not barred) dark rufous.

Harlan's Hawk

B. j. harlani (Audubon, 1830). Includes B. cooperi Cassin, 1856. Considered invalid by Palmer (Palmer 1988f), who attributed variation to polymorphism, but see Mindell (Mindell 1983a). Breeds from central Alaska through Yukon to n. British Columbia; winters chiefly in Great Plains and w. Midwest, south to Gulf Coast; some winter to Pacific coast [type locality = St. Francisville, Louisiana]. Polymorphic, although dark-morph birds predominate and gradation between dark and light morphs is continuous (Wheeler 2003b). Tail distinctive: rectrices whitish or gray mottled or streaked longitudinally with black, at times tinged reddish or light brown.


EBIRD GROUP (POLYTYPIC)

Red-tailed Hawk (calurus/alascensis) Buteo jamaicensis calurus/alascensis

Available illustrations of subspecies in this group

SUBSPECIES

Buteo jamaicensis alascensis Scientific name definitions

Systematics History

B. j. alascensis Grinnell, 1909.

Distribution

Breeds in se. Alaska from Yakutat to Ketchikan; resident from there south to sw. British Columbia, including Queen Charlotte Is. and Vancouver I. [type locality = Glacier Bay, Alaska]; vagrant to n. California (Bolinas, 30 December 2006; P. Pyle in litt.).

Identification Summary

Polymorphic (Taverner 1936b); like B. j. borealis but rectrices with narrow, wavy bars throughout and underwings rich tawny or pale rufous; size much smaller than in adjacent B. j. calurus populations—e.g., “largest females smaller than almost all males from elsewhere in Canada” (Palmer 1988f:105).


SUBSPECIES

Buteo jamaicensis calurus Scientific name definitions

Systematics History

B. j. calurus Cassin, 1855. Includes B. montanus Gambel, 1846, B. j. suttoni Dickerman, 1993, B. j. lucansanus Coues, 1873, B. rufescentior Salvin and Godman, 1900, and B. j. socorroensis Ridgway, 1880.

Distribution

Breeds w. of Rocky Mts. from e. Alaska south to Arizona and New Mexico, with breeding range also extending eastward through n. Alberta to nw. Manitoba; resident from s. British Columbia and nw. Manitoba, southward; winters through s. Great Plains to w. Gulf of Mexico and south through Middle America [type locality = Ft. Webster, New Mexico]. B. j. suttoni Dickerman, 1993, subsumed here with calurus. Resident in Sierra de la Laguna, Baja California Sur.

Identification Summary

Polymorphic, with distinct dark, rufous, and light morphs but also numerous intermediates along a continuum. Like B. j. borealis but belly band heavier, buffy or tawny ventrally (less white); only subspecies with barring (not streaking) forming belly band; throat typically dark brown. Polymorphic birds resident on Isla Socorro in Revillagigedo archipelago, sw. of tip of Baja California peninsula, were described as subspecifically distinct, but Jehl and Parkes (Jehl and Smith 1970) reported “that socorroensis cannot be separated from calurus on the basis of color and the validity of socorroensis must rest on its more robust legs and feet.” Although asserting that “The diameter of its tarsi and toes is obviously greater,” they further remarked that “this is not revealed by standard linear measurements” and recommended “comparative measurements should be made on osteological material, which is not available for the island form.” Without such data, the subspecies' validity cannot be established. B. j. suttoni, here subsumed with calurus: Monomorphic; like light morph B. j. calurus but belly band weak (matching B. j. fuertesi) and barring on thigh paler; throat typically white; averages less mottled dorsally and perhaps consistently smaller than either B. j. calurus or B. j. fuertesi (Dickerman 1994).


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (borealis) Buteo jamaicensis borealis Scientific name definitions

Systematics History

B. j. borealis (Gmelin, 1788). Includes Falco leverianus Gmelin, 1788, F. aquilinus Barton, 1799, Accipiter ruficaudus Vieillot, 1807, B. ferruginicaudus Vieillot, 1807, B. gallinivorus Vieillot, 1816, B. americanus Vieillot, 1816, B. pictus Phillipi, 1899, and tentatively B. j. abieticola Todd, 1950.

Distribution

Breeds from sw. Alberta east to w. Hudson Bay, e. Québec, and Maritime Provinces and south from e. Texas east to n. Florida [type locality = South Carolina]; winters from n. Great Plains and s. New England south to e. Mexico; vagrant to Bermuda.

Identification Summary

Monomorphic. Dorsum dark brown mottled with rufous or white; tail largely unmarked chestnut with narrow white tip and narrow black subterminal band; remiges dark gray, whitish basally; primaries black, tips barred; secondaries barred and mottled; throat typically white; ventrum white; belly band of fuscous streaks; flanks occasionally barred rufous; underwing white or tawny with distinct dark patagial bar; male wing > 337 mm, female wing > 370 mm. The taxonomic status of B. j. abieticola is still a matter of debate, and it likely deserves recognition as a valid subspecies. After its original description by Todd (Todd 1950), it was subsequently recognized by Dickerman and Parkes (Dickerman and Parkes 1987) and Dickerman (Dickerman 1989a), yet some authors remained unconvinced of its validity because individuals showing the heavy markings Todd ascribed to it were not entirely restricted to the boreal region of e. Canada (Wheeler 2003b). As a result, this taxon has received relatively little attention until recently, when Liguori and Sullivan (Liguori and Sullivan 2014) attempted to shed some light on it, and engage the birding community to use modern tools, such as eBird, to document the occurence of these more heavily marked birds in the Lower 48 United States during migration and winter. Field marks were further elucidated and described in this paper, building off Todd's (Todd 1950) original description. More study is needed, but this taxon would appear to meet a similar standard to the others currently considered valid subspecies in North America. In addition to being more heavily marked on average than B. j. borealis, a suite of researchers is currently exploring the strong likelihood that abieticola could be polymorphic, further distinguishing it biologically from borealis.


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (Harlan's) Buteo jamaicensis harlani Scientific name definitions

Systematics History

B. j. harlani (Audubon, 1830). Includes B. cooperi Cassin, 1856. Considered invalid by Palmer (Palmer 1988f), who attributed variation to polymorphism, but see Mindell (Mindell 1983a).

Distribution

Breeds from central Alaska through Yukon to n. British Columbia; winters chiefly in Great Plains and w. Midwest, south to Gulf Coast; some winter to Pacific Coast [type locality = St. Francisville, Louisiana].

Identification Summary

Polymorphic, although dark-morph birds predominate and gradation between dark and light morphs is continuous (Wheeler 2003b). Tail distinctive: rectrices whitish or gray mottled or streaked longitudinally with black, at times tinged reddish or light brown.


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (Krider's) Buteo jamaicensis kriderii Scientific name definitions

Systematics History

B. j. kriderii Hoopes, 1873. Taxonomy in need of further study; see (Liguori and Sullivan 2010). Often considered the light morph extreme of B. j. borealis (Clark and Wheeler 2001), but kriderii characteristics are limited to a particular geographic region, and based on current knowledge, only kriderii adults are known to produce birds with these characters. This taxon doesn't fit neatly into modern subspecies definitions: currently kriderii does not occupy a breeding range completely apart from those of other subspecies. But it may have historically met that subspecies criterion before alteration of the Great Plains by humans, as postulated by (Liguori and Sullivan 2010), and it is currently being swamped out mostly by B. j. borealis to the north and east, but also by encroaching B. j. calurus in the west. Many birds show intermediate characters now in the range of kriderii, and it is increasingly difficult to find "classic" examples of this taxon (Liguori and Sullivan 2010). Whether this was always the case or things have changed is difficult to know.

Distribution

Breeds northern Great Plains from sc. Canada south to South Dakota, Wyoming; winters mainly southern Great Plains east to Mississippi River delta; scarce east to Southeast and Florida.

Identification Summary

Adult similar to B. j. borealis but typical examples have whiter head and belly, the latter often lacking markings altogether, fainter more rufous-tinged patagials sometimes lacking, and variably white-based dorsal tail, often tipped pale red. Upperparts average more spangled with white, especially scapulars, occasionally with strong rufous highlights.


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (fuertesi) Buteo jamaicensis fuertesi Scientific name definitions

Systematics History

B. j. fuertesi Sutton and Van Tyne, 1935.

Distribution

Resident from se. Arizona east to cen. Texas, south to Durango and east to Tamaulipas [type locality = 22 mi. s. of Alpine, Brewster Co., Texas].

Identification Summary

Monomorphic; like B. j. suttoni but whiter (less rufescent) ventrally; size of B. j. calurus.


EBIRD GROUP (POLYTYPIC)

Red-tailed Hawk (kemsiesi/hadropus) Buteo jamaicensis kemsiesi/hadropus


SUBSPECIES

Buteo jamaicensis hadropus Scientific name definitions

Systematics History

B. j. hadropus Storer, 1962.

Distribution

Resident from s. Durango and San Luis Potosí south to Isthmus of Tehuantepec [type locality = Chilpáncingo, Guerrero].

Identification Summary

Polymorphic; like B. j. calurus but belly band formed by a mix of bars and streaks; in light morph, ventrum white (not buffy or tawny); averages smaller than B. j. calurus (Palmer 1988f).


SUBSPECIES

Buteo jamaicensis kemsiesi Scientific name definitions

Systematics History

B. j. kemsiesi Oberholser, 1959.

Distribution

Resident from Chiapas south to n. Nicaragua [type locality = Tegucigalpa, Honduras].

Identification Summary

Polymorphic; like B. j. fuertesi but belly band absent or faint, flanks barred with pale rufous, paler overall, and averages smaller (size of B. j. hadropus).


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (costaricensis) Buteo jamaicensis costaricensis Scientific name definitions

Systematics History

B. j. costaricensis Ridgway, 1874.

Distribution

Resident in highlands of Costa Rica and w. Panamá [type locality = Costa Rica].

Identification Summary

Monomorphic; like light morph B. j. jamaicensis but larger (size of B. j. hadropus), belly band dark rufous mottled with black, and thighs solid (not barred) dark rufous.


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (fumosus) Buteo jamaicensis fumosus Scientific name definitions

Systematics History

B. j. fumosus Nelson, 1898.

Distribution

Resident on Tres Marías Islands off Nayarit [type locality = Isla María Madre, Nayarit].

Identification Summary

Monomorphic; like light morph B. j. calurus but duskier dorsally, thighs heavily barred, rustier ventrally; throat typically dark (Grant 1965a).


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (socorroensis) Buteo jamaicensis socorroensis Scientific name definitions

Distribution

Socorro I (Revillagigedo Is), off W Mexico.

EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (umbrinus) Buteo jamaicensis umbrinus Scientific name definitions

Systematics History

B. j. umbrinus Bangs, 1901. Includes B. j. solitudinus Barbour, (Barbour 1935).

Distribution

Resident in peninsular Florida [type locality = Myakka, Manatee Co., Florida].

Identification Summary

Monomorphic; like light morph B. j. borealis but rectrices with dark barring near shafts. Birds from Cuba are purportedly smaller (B. j. “solitudinus”) but otherwise do not differ. Wing chord values listed by Barbour (Barbour 1935) and Friedmann (Friedmann 1950a) suggest broad overlap with birds from Florida.


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (jamaicensis) Buteo jamaicensis jamaicensis Scientific name definitions

Systematics History

B. j. jamaicensis (Gmelin, 1788). Includes B. fulvus Vieillot, 1807, and B. tropicalis Verrill and Verrill, 1909.

Distribution

Resident in Jamaica, Hispaniola, Puerto Rico, and Virgin Is. [type locality = Jamaica].

Identification Summary

Monomorphic; similar to light morph B. j. borealis but small (male wing < 340 mm; female wing < 371 mm), dorsum less mottled, belly band heavy and black, rectrices lack white tip, and thighs always barred rufous.


EBIRD GROUP (MONOTYPIC)

Red-tailed Hawk (solitudinis) Buteo jamaicensis solitudinis Scientific name definitions

Distribution

Bahamas, Cuba and I of Pines.

Related Species

Nearest relatives unclear. On the basis of morphological similarity, Buteo jamaicensis may be part of a larger cosmopolitan radiation that includes B. buteo (the Common Buzzard of Eurasia), B. augur (the Augur Buzzard of sub-Saharan Africa), B. rufofuscus (the Jackal Buzzard of the African cape), and B. ventralis (the Rufous-tailed Hawk of Patagonia). A recent molecular phylogeny (Riesing et al. 2003) recovered a sister relationship between B. jamaicensis and B. ventralis and between B. augur and B. rufofuscus, but these pairings are in separate (more-or-less) New World and Old World clades, the latter of which includes B. buteo in a more basal position. However, a strict consensus tree presented by Riesing et al. (Riesing et al. 2003) shows a polytomy at the branches separating the lineage including B. jamaicensis + B. ventralis and the lineage including B. buteo and B. augur + B. rufofuscus, hinting that a closer relationship may exist.

Rarely, may interbreed and produce offspring with Swainson's Hawk (Hull et al. 2007a).

In a broader context, buteoine hawks, including genus Buteo, are sister to a radiation including Haliaeeatus eagles and Haliastur kites (Lerner and Mindell 2005).

Hybridization

Hybrid Records and Media Contributed to eBird

  • Red-shouldered x Red-tailed Hawk (hybrid) Buteo lineatus x jamaicensis
  • Red-tailed x Rough-legged Hawk (hybrid) Buteo jamaicensis x lagopus
  • Red-tailed x Ferruginous Hawk (hybrid) Buteo jamaicensis x regalis

Fossil History

Widely recorded in late Pleistocene and Holocene of North America, and in the West Indies (Downs et al. 1958, Brodkorb 1964a, Brodkorb 1964b, Parmalee 1967a, Howard 1971b, Parmalee 1977, Campbell 1980, Guthrie 1980, Guthrie 1992, Ritchie 1980b, Rea and Hargrave 1984, Emslie 1985b, Emslie and Heaton 1987).

Brodkorb (Brodkorb 1964a) lists 8 extinct species in the genus Buteo. However, the generic assignment of these species needs to be reaffirmed. Several of the species are long-legged eagles most likely of an undescribed genus (R. Chandler pers. comm.). The fossils are all from deposits in the Great Plains. The earliest records are from the Chadronian-Orellan boundary North American Land Mammal Age [NALMA] 31 million yr before present [mybp] to the early Hemphillian NALMA (9 mybp). There are additional Buteo sp. records throughout the Neogene (e.g., see Bickart 1990b: 40). One record from the late Hemphillian NALMA (4.5–5 mybp) was the size of B. j. harlani (Becker 1985d: 133).

Red-tailed Hawk Figure 2. Breeding distribution of the Red-tailed Hawk by subspecies
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Figure 2. Breeding distribution of the Red-tailed Hawk by subspecies

Approximate breeding distribution of Red-tailed Hawk races: HA = harlani, AL = alascensis, CA = calurus, KR = “kriderii,” BO = borealis, FUE = fuertesi, SO = soccorroensis, HAD = hadropus, FU = fumosus, UM = umbrinus, SOL = solitudinus, JA = jamaicensis, KE = kemsiesi, CO = costaricensis. Adapted from Johnsgard (1990).

Red-tailed Hawk Juvenile Harlan's Hawk, British Columbia, January.
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Juvenile Harlan's Hawk, British Columbia, January.

Aldergrove, BC. The following link is to this contributor's Flickr stream or website. http://www.flickr.com/photos/waslin/, Jan 19, 2009; photographer Wes Aslin

Recommended Citation

Preston, C. R. and R. D. Beane (2020). Red-tailed Hawk (Buteo jamaicensis), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.rethaw.01