Buckley's forest falcon (''Micrastur buckleyi''), also called lesser collared forest-falcon and Traylor's forest-falcon, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

bird of prey Birds of prey or predatory birds, also known as raptors, are hypercarnivorous bird species that actively hunt and feed on other vertebrates (mainly mammals, reptiles and other smaller birds). In addition to speed and strength, these predat ...

in subfamily Herpetotherinae of family Falconidae, the

falcon Falcons () are birds of prey in the genus ''Falco'', which includes about 40 species. Falcons are widely distributed on all continents of the world except Antarctica, though closely related raptors did occur there in the Eocene. Adult falcons ...

s and caracaras. It is found in Brazil, Eucador, Peru, and possibly Colombia and Venezuela.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. 30 January 2023. Species Lists of Birds for South American Countries and Territories. https://www.museum.lsu.edu/~Remsen/SACCCountryLists.htm retrieved January 30, 2023

Taxonomy and systematics

Buckley's forest falcon was previously considered to be a variant of the

collared forest falcon The collared forest falcon (''Micrastur semitorquatus'') is a species of bird of prey in the family Falconidae. It is the largest member of the Micrastur genus and a common inhabitant of tropical rainforests in Latin America. Hiding in the dens ...

(''M. semitorquatus''). The two of them and the slaty-backed forest falcon (''M. mirandollei'') are

sister species In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 30 January 2023. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved January 30, 2023 It is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

Description

Buckley's forest falcon is long. Its wingspan is . Adult males have black upperparts with a white collar. Their cheeks, throat, and underparts are white and unmarked. Their tail is black with three narrow white bars on the inner feathers and four on the outer ones. Their iris is dark brown, their

cere The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for food ...

, lores, and bare skin around the eye are dull greenish, and their legs and feet are yellowish. Adult females are like males with the addition of white spots on their

scapulars The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either ...

and secondaries. Juveniles are also black above but have a buffy breast and dark bars on the belly.Bierregaard, R. O., P. F. D. Boesman, and J. S. Marks (2020). Buckley's Forest-Falcon (''Micrastur buckleyi''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.buffal1.01 retrieved February 12, 2023

Distribution and habitat

Buckley's forest falcon is known from only a few specimens, photographs, and sightings. Specimens confirm its presence in extreme western Brazil, eastern Ecuador, and eastern Peru. A few sight records in Colombia and Venezuela lead the South American Classification Committee of the

American Ornithological Society The American Ornithological Society (AOS) is an ornithological organization based in the United States. The society was formed in October 2016 by the merger of the American Ornithologists' Union (AOU) and the Cooper Ornithological Society. Its m ...

to classify it as hypothetical in those two countries. Most of the records are from lowland tropical and subtropical forest at elevations between but one specimen was collected at in Ecuador and there is a record at in Peru.

Behavior

Movement

Buckley's forest falcon is assumed to be a year-round resident.

Feeding

Almost nothing is known about the diet or hunting technique of Buckley's forest falcon. One specimen had a small ''

Mesomys ''Mesomys'' is a genus of South American spiny rats in the family Echimyidae. The genus name ''Mesomys'' derives from the two ancient greek words (), meaning "middle of, between", and (), meaning "mouse, rat". It refers to the fact that this ...

'' arboreal rat in its stomach. The species' small feet suggest that birds are only a minor part of its diet.

Breeding

Sightings of Buckley's forest falcon fledglings suggest that its breeding season includes April to early August. Nothing else is known about its breeding biology though it is assumed to nest in tree cavities like other ''Micrastur'' forest falcons.

Vocalization

The most common Buckley's forest falcon vocalization is "a far-carrying, nasal "eeok, oow" or "eeok, oow...ow", repeated...for long periods, mainly at dawn." It also occasionally makes "a long rising series of "kaw" notes followed by 2-3 falling "aauw" notes".

Status

The IUCN has assessed Buckley's forest falcon as being of Least Concern, though it has a limited range and an unknown population size that is believed to be decreasing. No immediate threats have been identified. It is poorly known and considered to be rare. "Evidence suggest that species is not immediately threatened; however, at least in part of range, habitat is in process of being cleared."

References

{{Taxonbar, from=Q1193073 Buckley's forest falcon Birds of the Ecuadorian Amazon Birds of the Peruvian Amazon Buckley's forest falcon Buckley's forest falcon Taxonomy articles created by Polbot