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White-breasted hawk | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Accipitriformes |
Family: | Accipitridae |
Genus: | Accipiter |
Species: | A. chionogaster |
Binomial name | |
Accipiter chionogaster (Kaup, 1852) | |
Synonyms | |
Accipiter striatus chionogaster |
The white-breasted hawk (Accipiter chionogaster) is a small hawk found from southern Mexico to Nicaragua. It is usually considered a subspecies of the sharp-shinned hawk by most taxonomists, including the American Ornithological Society, but the taxonomy is far from resolved, with some authorities considering the southern taxa to represent three separate species: white-breasted hawk (A. chionogaster), plain-breasted hawk (A. ventralis), and rufous-thighed hawk (A. erythronemius).
The breeding range of the white-breasted hawk and the sharp-shinned hawk is entirely allopatric, although the wintering range only partially overlaps. This allopatry combined with differences in plumage (see appearance) and, apparently, certain measurements, has been the background for the split, but hard scientific data is presently lacking (AOU). Disregarding field guides, most material published in recent years (e.g. AOU, Ferguson-Lees et al. p. 586, and Dickinson et al.) has therefore considered all to be members of a single widespread species – but not without equivocation: Ferguson-Lees et al. say that if they were to make a world list, they would include the three taxa as separate species (p. 75), and the AOU's comment includes the note "split almost certainly good". [1] [2]
Storer (1952) suggested that the southernmost populations of sharp-shinned hawk were paler below, thus approaching chionogaster. [3] This has also been reflected in recent guides, where A. s. madrensis of southern Mexico is described as being relatively pale below (compared to more northern subspecies), but if this is a sign of intergradation with chionogaster or a north-south cline which includes both the members of the nominate group and chionogaster remains unclear.
The two syntype specimens of Nisus (seu Accipiter) chionogaster Kaup (Proc. Zool. Soc. London, 1851, p.41.) are held in the collections of National Museums Liverpool at World Museum, with accession numbers D392 (female adult) and D392a (male adult). The specimens were collected in Cobán, Guatemala in June 1843 by Adolphe Delattre and came to the Liverpool national collection via the 13th Earl of Derby’s collection which was bequeathed to the city of Liverpool.
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This is a small Accipiter hawk, with males 23 to 30 cm (9.1 to 11.8 in) long, with a wingspan of 42 to 58 cm (17 to 23 in) and weight from 82–115 g (2.9–4.1 oz). As common in Accipiter hawks, females are distinctly larger in size, averaging some 30% longer, and with a weight advantage of more than 50% being common. The female measures 29 to 37 cm (11 to 15 in) in length, has a wingspan of 58 to 68 cm (23 to 27 in) and weighs 150 to 219 g (5.3 to 7.7 oz). The wings measure 14.1–22.9 cm (5.6–9.0 in) each, the tail is 12–19 cm (4.7–7.5 in) long and the tarsus is 4.5–5.9 cm (1.8–2.3 in). Measurements given here are for the northern group, but they are comparable for the remaining species in the group. [4] Adults have short broad wings and a medium-length tail banded in blackish and gray with the tip varying among individuals from slightly notched through square to slightly rounded (often narrowly tipped white). The remiges (typically only visible in flight) are whitish barred blackish. The legs are long and very slender (hence the common name) and yellow. The hooked bill is black and the cere is yellowish. The remaining plumage varies depending on group:
The white-breasted hawk resembles the sharp-shinned hawk, but upperparts darker (often appears almost black), thighs whitish-buff and underparts and cheeks entirely white. Juveniles have darker upperparts and distinctly finer streaking below than juveniles of the nominate group.
It occurs in highlands from far southern Mexico (Chiapas and Oaxaca), through Honduras, Guatemala and El Salvador, to Nicaragua. It is, as far as known, resident, but some local movements may occur.
They are most commonly found in pine and pine-oak habitats, regularly visiting neighbouring cloud forest, tropical dry forest and farmland; mainly at altitudes of 300–3,000 m (980–9,840 ft).
These birds surprise and capture most of their prey from cover or while flying quickly through dense vegetation. They are adept at navigating dense thickets, although this hunting method is often hazardous to the hawk. The great majority of this hawk's prey are small birds, especially various songbirds such as wood-warblers, wrens, and thrushes. Typically, males will target smaller birds, such as wood-warblers, and females will pursue larger prey, such as doves, leading to a lack of conflict between the sexes for prey. They often pluck the feathers off their prey on a post or other perch. Rarely, white-breasted hawks will also eat lizards, bats, and large insects.
White-breasted hawks construct a stick nest. Clutches of 2 to 4 eggs have been recorded. The eggs measure 38 mm × 31 mm (1.5 in × 1.2 in) and weigh about 19 g (0.67 oz). The incubation period is thought to average at about 30 days. After hatching, the young are brooded for 16 to 23 days by the female, while the male defends the territory and catches prey. The young fledge at the age of about a month and rely on their parents for feeding and protection another four weeks. The breeding behavior of the taxa are comparably poorly known, but based on the available knowledge they appear to differ little from that of the sharp-shinned hawk.
The situation for white-breasted hawk is more problematic due to its limited range, although it, at least locally, remains fairly common.
The sharp-shinned hawk or Northern sharp-shinned hawk, commonly known as a sharpie, is a small hawk, with males being the smallest hawks in the United States and Canada, but with the species averaging larger than some Neotropical species, such as the tiny hawk. The taxonomy is far from resolved, with some authorities considering the southern taxa to represent three separate species: white-breasted hawk, plain-breasted hawk, and rufous-thighed hawk. The American Ornithological Society keeps all four variations conspecific.
Cooper's hawk is a medium-sized hawk native to the North American continent and found from southern Canada to Mexico. This species is a member of the genus Accipiter, sometimes referred to as true hawks, which are famously agile, relatively small hawks common to wooded habitats around the world and also the most diverse of all diurnal raptor genera. As in many birds of prey, the male is smaller than the female. The birds found east of the Mississippi River tend to be larger on average than the birds found to the west. It is easily confused with the smaller but similar sharp-shinned hawk.
Accipiter is a genus of birds of prey in the family Accipitridae. With 49 recognized species it is the most diverse genus in its family. Most species are called goshawks or sparrowhawks, although almost all New World species are simply known as hawks. They can be anatomically distinguished from their relatives by the lack of a procoracoid foramen. Two small and aberrant species usually placed here do possess a large procoracoid foramen and are also distinct as regards DNA sequence. They may warrant separation in the old genus Hieraspiza.
The American redstart is a New World warbler. It is unrelated to the Old World (common) redstart.
The dark chanting goshawk is a bird of prey in the family Accipitridae which is found across much of sub-Saharan Africa and southern Arabia, with an isolated and declining population in southern Morocco.
The besra, also called the besra sparrowhawk, is a bird of prey in the family Accipitridae.
The yellow-throated warbler is a small migratory songbird species in the New World warbler family (Parulidae) found in temperate North America.
The Levant sparrowhawk is a small bird of prey. It measures 32–38 cm (13–15 in) in length with a wingspan of 65–75 cm (26–30 in). The female is larger than the male, but the difference is not as marked as with Eurasian sparrowhawk. The adult male is blue-grey above, with dark wingtips, and barred reddish below.
The eastern (pale) chanting goshawk, or Somali chanting goshawk, is a bird of prey of East Africa.
The tiny hawk is a small diurnal bird of prey found in or near forests, primarily humid, throughout much of the Neotropics. It is primarily a bird-eater, and is known to prey on hummingbirds.
The bicolored hawk is a species of bird of prey in the family Accipitridae. It is found in forest, woodland, second growth, plantations, and wooded savanna in southeastern Mexico, Central America, and northern and central South America. Though generally uncommon, it is the most common species of Accipiter in most of its range, but it does not occur at altitudes above 2,700 metres (8,900 ft) such as the highest parts of the Andes.
The chestnut-flanked sparrowhawk is a small west African species of sparrowhawk in the family Accipitridae.
The red-thighed sparrowhawk, alternatively known as the red-legged sparrowhawk or western little sparrowhawk, is a species of sparrowhawk in the family Accipitridae from western and northern central Africa.
The rufous-breasted sparrowhawk, also known as the rufous-chested sparrowhawk and as the red-breasted sparrowhawk, is a species of bird of prey in the family Accipitridae. It is found in Angola, Democratic Republic of the Congo, Eritrea, Eswatini, Ethiopia, Kenya, Lesotho, Malawi, Mozambique, Rwanda, South Africa, South Sudan, Tanzania, Uganda, Zambia, and Zimbabwe.
The Congo serpent eagle is a species of bird of prey in the family Accipitridae. It is the only member of the monotypic genus Dryotriorchis, although it was formerly placed in Circaetus. This species is distributed across the African tropical rainforest, including upper and lower Guinean forests. This serpent eagle specializes in hunting in these forests’ dark understories. It has two subspecies, the nominate subspecies Dryotriorchis spectabilis spectabilis and Dryotriorchis spectabilis batesi. Though monotypic, it appears to be very closely related to Circaetus. This hawk is a medium-sized bird with distinctive short, rounded wings and a long, rounded tail. It is varying shades of brown on its back and has a slight crest. Its breast is white with variable amounts of a rufous wash and, in the nominate subspecies, is covered in round, blackish spots. The subspecies D. s. batesi only has these dots on its flanks. The Congo serpent eagle closely resembles Cassin's hawk-eagle, and some ornithologists believe that this likeness is a rare example of avian mimicry. It is a very vocal raptor, and often is one of the most heard species in its habitat.
The double-toothed kite is a species of bird of prey in subfamily Accipitrinae, the "true" hawks, of family Accipitridae. It is found from central Mexico through Central America into much of northern and eastern South America.
The red-chested goshawk is a medium-size hawk of West Africa. It is often considered conspecific with the African goshawk.
The plain-breasted hawk is a small hawk described from Venezuela to western Bolivia. It is usually considered a subspecies of the sharp-shinned hawk by most taxonomists, including the American Ornithological Society, but the taxonomy is far from resolved, with some authorities considering the southern taxa to represent three separate species: white-breasted hawk, plain-breasted hawk, and rufous-thighed hawk.
The rufous-thighed hawk is a small hawk found from southern Brazil and southeastern Bolivia to Paraguay, Uruguay and northern Argentina. It is usually considered a subspecies of the sharp-shinned hawk by most taxonomists, including the American Ornithological Society, but the taxonomy is far from resolved, with some authorities considering the southern taxa to represent three separate species: white-breasted hawk, plain-breasted hawk, and rufous-thighed hawk.
The gray hawk or Mexican goshawk is a smallish raptor found in open country and forest edges. It is sometimes placed in the genus Asturina as Asturina plagiata. The species was split by the American Ornithological Society (AOU) from the gray-lined hawk. The gray hawk is found from Costa Rica north into the southwestern United States.