Pseudastur albicollis

Life-forms

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Cladus: Sarcopterygii
Cladus: Rhipidistia
Cladus: Tetrapodomorpha
Cladus: Eotetrapodiformes
Cladus: Elpistostegalia
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Archosauromorpha
Cladus: Crurotarsi
Divisio: Archosauria
Cladus: Avemetatarsalia
Cladus: Ornithodira
Subtaxon: Dinosauromorpha
Cladus: Dinosauriformes
Cladus: Dracohors
Cladus: Dinosauria
Ordo: Saurischia
Cladus: Eusaurischia
Subordo: Theropoda
Cladus: Neotheropoda
Cladus: Averostra
Cladus: Tetanurae
Cladus: Avetheropoda
Cladus: Coelurosauria
Cladus: Tyrannoraptora
Cladus: Maniraptoromorpha
Cladus: Maniraptoriformes
Cladus: Maniraptora
Cladus: Pennaraptora
Cladus: Paraves
Cladus: Eumaniraptora
Cladus: Avialae
Infraclassis: Aves
Cladus: Avebrevicauda
Cladus: Pygostylia
Cladus: Ornithothoraces
Cladus: Ornithuromorpha
Cladus: Carinatae
Parvclassis: Neornithes
Cohors: Neognathae
Cladus: Neoaves
Ordo: Accipitriformes

Familia: Accipitridae
Genus: Pseudastur
Species: Pseudastur albicollis
Subspecies: P. a. albicollis – P. a. costaricensis – P. a. ghiesbreghti – P. a. williaminae
Name

Pseudastur albicollis (Latham, 1790
Synonyms

Falco albicollis (protonym)
Leucopternis albicollis

References

Latham, J. 1790. Index ornithologicus, sive systema ornithologiæ; complectens avium divisionem in classes, ordines, genera, species, ipsarumque varietates: adjectis synonymis, locis, descriptionibus, &c. Volumen I: pp. i–xviii, 1–466. Londini. (Leigh & Sotheby). BHL Reference page. : 36

Vernacular names
čeština: Káně pralesní
English: White Hawk
español: Busardo blanco
Nāhuatl: Iztāccuāuhtli
polski: Białostrząb duży

The white hawk (Pseudastur albicollis) is a bird of prey breeding in the tropical New World of the family Accipitridae. Though it is commonly placed in the subfamily Buteoninae, the validity of this group is doubtful and currently under review.
Description
Jordanal - El Valle, Panama
Adult Pseudastur albicollis costaricensis in Honduras
Adult Pseudastur albicollis ghiesbreghti

The adult white hawk ranges from 46–56 cm (18–22 in) long with very broad wings and has a white head, body and underwings. The upper wings are black, and the very short tail is black with a broad white band. The bill is black and the legs are yellow.

The sexes are similar, but females are larger and heavier—840 g (1.85 lb) compared to the male's 650 g (1.43 lb). Immature birds have extensive black spotting on the upperparts and dark-streaked whitish underparts.

The call of the white hawk is a plaintive kerwee.
Subspecies

There are four subspecies:

Pseudastur albicollis ghiesbreghti – Southern Mexico to Nicaragua

Entirely white, except for black markings on the outer primaries, and a black sub-terminal tail bar. The eyes are yellow.

Pseudastur albicollis costaricensis – Honduras to Panama and Colombia.

Similar to ghiesbreghti but with more distinct black markings on the wings and tail. The eyes are brown.

Pseudastur albicollis williaminae – Locally in north-western Colombia and western Venezuela.

Wing feathers are more heavily marked with black, and it has black streaks on the crown and collar. The tail band is broader and the eyes are brown.

Pseudastur albicollis albicollis – Northern Colombia and central Venezuela to Brazil.

Smaller than the northern forms and the wings are mostly black, with white markings. The black tail band extends to the base of the tail and the eyes are brown.

All subspecies look mainly white from below. The identity of the birds discovered in 2000/2001 in the Serranía de las Quinchas of central Colombia [3] is unclear.
Systematics

The white hawk was described by John Latham: in English (1787) as the "white-necked falcon",[4] and in Latin (1790) as Falco albicollis,[5] with locality "Cayenne". Around 1850, Edward Blyth created the genus Pseudaster, with "Falco pæcilonotus Cuvier" as the type and "F.skotopterus Pr. Max." as a synonym.[6] In his Genera of Birds, Gray treats them both as Buteos, listing B. albicollis in the main text and B. pæcilonotus in the index.

Peters' influential 1931 checklist placed the white hawk in Kaup's genus Leucopternis, listing five subspecies: L. albicollis albicollis, L. a. ghiesbrechti, L. a. costaricensis, L. a. occidentalis, and L. a. polionota.[7] During the 20th century, some authors treated the grey-backed hawk occidentalis as a subspecies of L. albicollis, whilst others recognized it as a separate species.[8]

In the first decade of the 2000s Leucopternis was found to be polyphyletic, and in 2012 the American Ornithologists' Union separated the white hawk and its relatives under the old name Pseudaster.[9]

DNA analysis found that the subspecies P. a. albicollis is sister to P. a. polionotus, and the trans-Andean P. a. ghiesbreghti and P. a. costaricensis are more closely related to P. occidentalis than they are to P. a. albicollis.[8]
Distribution and ecology

This is a bird of lowland forest and other woodlands. It ranges from southern Mexico through Central and South America to Peru, Bolivia and Brazil. It also breeds on Trinidad. The white hawk's range in central South America is the entire Amazon basin, from the Andes on the west to the Guianas on the Atlantic on the northeast, and to the transition lands to the south. A widespread species, it is usually not common, but the IUCN considers it not to be globally threatened due to the large extent of its range.[1]

The white hawk feeds mainly on reptiles (such as lizards and snakes, including the eastern coral snake) with some insects (such as beetles and grasshoppers), crabs, amphibians and mammals (including rats, squirrels, small opossums and bats), caught in a sortie from a perch.[10][11][12] Researchers have documented the white hawk feeding on a number of bird species including the keel-billed toucan, the mottled owl, the white-breasted wood wren and the great tinamou.[10] They may feed on young and weak birds, as well.[12] Though rare, there is some evidence that this hawk may occasionally feed on fish.[10] One researcher in Suriname found remains of a fish in a white hawk's stomach.[10] It associates with foraging groups of tufted capuchin monkeys (Cebus apella) and South American coatis (Nasua nasua) to snatch prey startled by these animals.[13] This species is often seen soaring, and has a spectacular aerial courtship display.

It builds a large stick platform nest in a tree[14] and usually lays one dark-blotched blue-white egg. An attended nest was observed in Ecuador in mid-August.[15]
Footnotes

BirdLife International (2020). "Pseudastur albicollis". IUCN Red List of Threatened Species. 2020: e.T22695786A168802065. doi:10.2305/IUCN.UK.2020-3.RLTS.T22695786A168802065.en. Retrieved 12 November 2021.
Gill F, D Donsker & P Rasmussen (Eds). 2020. IOC World Bird List (v10.2). doi : 10.14344/IOC.ML.10.2.
Laverde-R. et al. (2005)
Latham (1787), pp. 30–31, species no. 101
Latham (1790), p. 36, species no. 81
Blyth ("1849" [1852]), p. 24
Peters 1931, vol. 1, pp. 241–242
Magnier & Schulenberg (2013), section Systematics
Chesser, et al. (2012)
"White Hawk | the Peregrine Fund".
Ferguson-Lees, J. & Christie, D.A. & Franklin, K. & Mead, D. & Burton, P.. (2001). Raptors of the world. Helm Identification Guides.
"Pseudastur albicollis (White Hawk)" (PDF). Retrieved 2023-10-23.
de Mello Beisiegel (2007)
E.g. Ceiba sp.: Cisneros-Heredia (2006)

Cisneros-Heredia (2006)

References

Chesser, R. Terry; et al. (2012). "Fifty-third Supplement to the American Ornithologists' Union Check-list of North American Birds" (PDF). The Auk. 129 (3): 573–588. doi:10.1525/auk.2012.129.3.573. S2CID 198159113.
Cisneros-Heredia, Diego F. (2006): Notes on breeding, behaviour and distribution of some birds in Ecuador. Bull. B.O.C. 126(2): 153–164. PDF fulltext
de Mello Beisiegel, Beatriz (2007): Foraging Association between Coatis (Nasua nasua) and Birds of the Atlantic Forest, Brazil. Biotropica 39(2): 283–285. doi:10.1111/j.1744-7429.2006.00255.x (HTML abstract)
ffrench, Richard; O'Neill, John Patton & Eckelberry, Don R. (1991): A guide to the birds of Trinidad and Tobago (2nd edition). Comstock Publishing, Ithaca, N.Y.. ISBN 0-8014-9792-2
Hilty, Steven L. (2003): Birds of Venezuela. Christopher Helm, London. ISBN 0-7136-6418-5
Latham, John (1787): Supplement to the General Synopsis of Birds. London; Leigh & Sotheby. [1]
Latham, John (1790): Index ornithologicus, sive, Systema ornithologiae. London; Leigh & Sotheby.
Laverde-R., Oscar; Stiles, F. Gary & Múnera-R., Claudia (2005): Nuevos registros e inventario de la avifauna de la Serranía de las Quinchas, un área importante para la conservación de las aves (AICA) en Colombia [New records and updated inventory of the avifauna of the Serranía de las Quinchas, an important bird area (IBA) in Colombia]. Caldasia 27(2): 247-265 [Spanish with English abstract]. PDF fulltext
Magnier, B. and T. S. Schulenberg (2013). White Hawk (Pseudastur albicollis), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. DOI 10.2173/nb.whihaw1.01.
Peters, James Lee (1931): Check-list of birds of the world, volume 1. [2]