Black-chested buzzard-eagle
   HOME

TheInfoList



OR:

The black-chested buzzard-eagle (''Geranoaetus melanoleucus'') is a
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 predators h ...
of the
hawk Hawks are bird of prey, birds of prey of the family Accipitridae. They are widely distributed and are found on all continents except Antarctica. * The subfamily Accipitrinae includes goshawks, sparrowhawks, sharp-shinned hawks and others. Th ...
and
eagle Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...
family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
(
Accipitridae The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-s ...
). It lives in open regions of
South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
. This
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 ...
is also known as the black buzzard-eagle, the gray buzzard-eagle or analogously with "eagle" or "eagle-buzzard" replacing "buzzard-eagle", or as the Chilean blue eagle. It is sometimes placed in the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''
Buteo ''Buteo'' 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 the New World (Etymology: ''Buteo'' is the Latin na ...
''.


Description

This is a huge eagle-like "
buzzard Buzzard is the common name of several species of birds of prey. ''Buteo'' species * Archer's buzzard (''Buteo archeri'') * Augur buzzard (''Buteo augur'') * Broad-winged hawk (''Buteo platypterus'') * Common buzzard (''Buteo buteo'') * Eastern ...
" ("hawk" in American terminology). It has a total length of and a wingspan of .Blake, E. R. 1977. ''Manual of neotropical birds. Volume 1''. University of Chicago Press, Chicago, Illinois. In the nominate race, males averaged and females averaged , with a range between both of . In the linearly slightly smaller ''G. m. australis'' subspecies, a male weighed and a female weighed , indicating the bulk of the two races is roughly the same.''CRC Handbook of Avian Body Masses, 2nd Edition'' by John B. Dunning Jr. (Editor). CRC Press (2008), . It is noted for its bulky, powerful-looking build. It is rather long- and broad-winged and the slightly tapering tail is short by comparison and colored black, with grey tips in fresh plumage. When perched, the wings cover the tail almost completely, giving the bird a unique near-tailess appearance when perched. The adult has a white underside, sometimes with fine blackish stripes; its upperparts are dark grey with a blackish, brownish or bluish hue. The feathers of the neck and the lowest dark feathers of the breast are somewhat elongated. Adults have an ash-grey-and-white zone on the wings, the silvery white seen clearly from afar. The female is distinguished by a reddish-cinnamon hue to the upper- and underwing secondaries and is considerably larger than the male. Among standard measurements, males possess a wing chord of , a
tail The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...
of , a culmen of and a tarsus of . In comparison, females have a wing chord of , a
tail The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...
of , a culmen of and a tarsus of . The immature
plumage Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...
is reminiscent of that of the
great black hawk The great black hawk (''Buteogallus urubitinga'') is a bird of prey in the family Accipitridae, which also includes the eagles, hawks, and Old World vultures. Taxonomy The great black hawk was formally described in 1788 by the German naturalist ...
(''Buteogallus urubitinga''). Its upperparts are deep brown, sometimes almost black, and it has no light wing patch. The underside is white or light
buff Buff or BUFF may refer to: People * Buff (surname), a list of people * Buff (nickname), a list of people * Johnny Buff, ring name of American world champion boxer John Lisky (1888–1955) * Buff Bagwell, a ring name of American professional ...
with heavy dark streaks on the breast and dark bars on the belly and thighs. It does not acquire the full adult plumage until 4–5 years old. It is not very vocal, calling usually in flight and when close to the
nest A nest is a structure built for certain animals to hold eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of organic materia ...
. Some calls resemble a wild human laugh, others are a
curlew The curlews () are a group of nine species of birds in the genus ''Numenius'', characterised by their long, slender, downcurved bills and mottled brown plumage. The English name is imitative of the Eurasian curlew's call, but may have been in ...
-like whistle. Occasionally flying birds give a high-pitched vocalization "kukukukuku". The black-chested buzzard-eagle is readily identified in flight by its short wedge-shaped tail scarcely protruding from its long, broad
wings A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is expresse ...
. It is usually easy to make out the generally white underparts with the dark chest-band and tail if the birds are adult. Yet as this bird is usually encountered in the wild when it soars, you are less likely to see its grey upperparts.


Taxonomy and systematics

Its
scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
is
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
ized
Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
and means "black-and-white crane-eagle" or (if called ''Buteo melanoleucos'') "black-and-white buzzard": ''Geranoaetus'' comes from Ancient Greek ''géranos'' (γέρανoς), " crane" + ''aetós'' (ἆετός), "eagle". The "crane" reference is due to its grey upper wings and its loud cries. The alternative
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
name ''Buteo'' is simply the Latin term used for these hawks in
Ancient Rome In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 B ...
, translating as "buzzard" (in the European sense). ''melanoleucus'' is from Ancient Greek ''mélan-'' (μέλαν-), "black-" + ''leukós'' (λευκός), "white". This refers to the contrasting coloration when seen from below. When the black-chested buzzard-eagle was first described by
Louis Jean Pierre Vieillot Louis Pierre Vieillot (10 May 1748, Yvetot – 24 August 1830, Sotteville-lès-Rouen) was a French ornithologist. Vieillot is the author of the first scientific descriptions and Linnaean names of a number of birds, including species he collecte ...
in 1819, it was placed in the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''
Spizaetus ''Spizaetus'' is the typical hawk-eagle birds of prey genus found in the tropics of the Americas. It was however used to indicate a group of tropical eagles that included species occurring in southern and southeastern Asia and one representative ...
'', as ''Spizaetus melanoleucus''. Nowadays, however, the
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 "unispec ...
genus ''Spizastur'' is merged in ''Spizaetus'', and the
black-and-white hawk-eagle The black-and-white hawk-eagle (''Spizaetus melanoleucus'', formerly ''Spizastur melanoleucus'') is a bird of prey species in the eagle and hawk family (Accipitridae). It is found throughout a large part of tropical America, from southern Mexic ...
, originally described as by Vieillot three years earlier as ''Buteo melanoleucus'', is now known as ''Spizaetus melanoleucus''. The earlier use of the
specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
''melanoleucus'' for the black-and-white hawk-eagle technically precludes its use for the black-chested buzzard-eagle, except when it is placed in ''Geranoaetus''. In fact, in the mid-20th century ''Buteo fuscescens'' was the prevailing name for the black-chested buzzard-eagle for some years, but it was eventually dismissed as erroneous. This specific name was established – as ''Spizaetus fuscescens'' – by Vieillot for the immature of the black-chested buzzard-eagle at the very same time as he described the adult, because he could not believe that such differently-colored birds were
conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organ ...
. As the two birds are not placed in the same genus today, Article 59.3 of the ICZN Code applies. According to this, a junior homonym replaced before 1961 is ''not'' rendered permanently invalid (as junior homonyms usually are) if "the substitute name is not in use" – which has been the case after Amadon's 1963 revision. Hence, in this case the scientific name ''Buteo melanoleucus'' can apply, even though the black-and-white hawk-eagle was earlier described under exactly that name, while the senior homonym ''melanoleucus'' still applies to the latter species when placed in ''Spizaetus'' according to the usual ICZN rules. Consequently, the proper name to use for each bird has through a number of coincidences become the one the other species was described under.


Systematics

There are two
subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
: * Eastern black-chested buzzard-eagle, ''Geranoaetus melanoleucus melanoleucus'' (Vieillot, 1819) – SE South America from S and E
Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
(
Alagoas Alagoas (, ) is one of the 27 federative units of Brazil and is situated in the eastern part of the Northeast Region. It borders: Pernambuco (N and NW); Sergipe (S); Bahia (SW); and the Atlantic Ocean (E). Its capital is the city of Maceió. It ...
,
Rio de Janeiro Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a b ...
, and
São Paulo state SAO or Sao may refer to: Places * Sao civilisation, in Middle Africa from 6th century BC to 16th century AD * Sao, a town in Boussé Department, Burkina Faso * Saco Transportation Center (station code SAO), a train station in Saco, Maine, U.S ...
s) through
Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...
,
Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...
, and NE
Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
:Larger, Plain white below. * Western black-chested buzzard-eagle, ''Geranoaetus melanoleucus australis'' Swann, 1922
Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...
from NW
Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
( Mérida) through
Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...
( Cordillera Central, occasionally ranging into the Cordillera Occidental),
Ecuador Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...
,
Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...
,
Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...
,
Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...
, and W Argentina to
Tierra del Fuego Tierra del Fuego (, ; Spanish for "Land of the Fire", rarely also Fireland in English) is an archipelago off the southernmost tip of the South American mainland, across the Strait of Magellan. The archipelago consists of the main island, Isla G ...
:Smaller. White with fine dark barring below. The black-chested buzzard-eagle is allied to the ''
Buteo ''Buteo'' 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 the New World (Etymology: ''Buteo'' is the Latin na ...
'' hawks, and it is sometimes included with these. Other authors place it in the
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 "unispec ...
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Geranoaetus''. Though the former seems to be more appropriate from a
phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
standpoint, the latter is still used here, as much more research into phylogeny and hybridization has to take place before the correct
taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...
of the buteonines can be resolved. It stands to note that the taxonomic and systematic dispute goes back to the early-mid 20th century already. However, it seems there is no real reason to suppose that the lineage of the black-chested buzzard-eagle is North American in origin;
fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
s that might have been its ancestors at first sight differ in details and are more likely to belong to other buteonine lineages. Because of its buteonine lineage, this species and the closely related ''
Harpyhaliaetus ''Harpyhaliaetus'' is a former genus of eagles. Recent studies have shown that the solitary eagle The solitary eagle or montane solitary eagle (''Buteogallus solitarius'') is a large Neotropical eagle. It is also known as the black solitary e ...
'' are not considered "true eagles", as are '' Aquila'' eagles and " hawk-eagles", and are thus the largest extant type of the diverse buteonine lineage. This species could be close to the
white-tailed hawk The white-tailed hawk (''Geranoaetus albicaudatus'') is a large bird of prey species found in tropical and subtropical environments of the Americas. Description The white-tailed hawk is a large, stocky hawk. It is close in size to the Swainso ...
(''Buteo albicaudatus''), and perhaps to the grey-backed (''Leucopternis occidentalis''),
white White is the lightest color and is achromatic (having no hue). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully reflect and scatter all the visible wavelengths of light. White on ...
(''L. albicollis''), and
mantled hawk The mantled hawk (''Pseudastur polionotus'') is a South American species of bird of prey in the family Accipitridae. Taxonomy and evolution This hawk was formerly placed in the genus '' Leucopternis'' and was known as ''Leucopternis polionota'' ...
s (''L. polionotus'') which it resembles in habitus except for being larger. Its closest living relatives may well be the red-backed (''B. polyosoma'') and
Puna hawk The variable hawk (''Geranoaetus polyosoma'') is a polymorphic species of bird of prey in the family Accipitridae. It is widespread and often common in open habitats in western and southern South America, including the Falkland Islands. Its ta ...
s (''B. poecilochrous''). Particularly some populations of the former look like small black-chested buzzard-eagles. The barred hawk (''L. princeps'') looks similar to the black-chested buzzard-eagle in general color pattern, though the tail differs much in shape, size, and the bright white central band stands out. The relationship of the black-chested buzzard-eagle to the
prehistoric Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of ...
genera ''Titanohierax'' from the
Caribbean The Caribbean (, ) ( es, El Caribe; french: la Caraïbe; ht, Karayib; nl, De Caraïben) is a region of the Americas that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Se ...
and the Pan-American ''Amplibuteo'' also warrant more study. The crab-hawks (''
Buteogallus ''Buteogallus'' is a genus of birds of prey in the family Accipitridae. All members of this genus are essentially neotropical, but the distribution of a single species extends slightly into the extreme southwestern United States. Many of the sp ...
'') and the solitary "eagles" (''
Harpyhaliaetus ''Harpyhaliaetus'' is a former genus of eagles. Recent studies have shown that the solitary eagle The solitary eagle or montane solitary eagle (''Buteogallus solitarius'') is a large Neotropical eagle. It is also known as the black solitary e ...
'') seem to be allied with the latter, to the extent that these three genera might be united in ''Buteogallus''. That genus in the present restricted sense contains species also quite similar in habitus and size to the black-chested eagle-buzzard.


Fossil record

Some
fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
s have been placed in ''Geranoaetus'', but those from
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
have since been moved elsewhere: * ''"Geranoaetus" ales'', ''"G." contortus'' and ''"G." conterminus'' are now in ''Buteo''. * ''"Geranoaetus" fragilis'' (Fragile "eagle") and ''"G." milleri'' (Miller's "eagle") are now in ''Buteogallus''. The
type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...
s of the latter were at first erroneously believed to be of the black-chested eagle-buzzard. * ''"Geranoaetus" grinnelli'' (Grinnell's "eagle") is now in ''
Spizaetus ''Spizaetus'' is the typical hawk-eagle birds of prey genus found in the tropics of the Americas. It was however used to indicate a group of tropical eagles that included species occurring in southern and southeastern Asia and one representative ...
''. * ''"Geranoaetus" dananus'', originally described as ''"Aquila" danana'', is of rather unclear affiliations but probably belongs to the same lineage as the above. Bones indistinguishable from those of living black-chested buzzard-eagles were found in a spring deposit at the Baños de Ciego Montero in
Cienfuegos Province Cienfuegos () is one of the provinces of Cuba. The capital city of the province is also called Cienfuegos and was founded by French settlers in 1819. Overview Until 2011 Cienfuegos was the smallest province in Cuba (excluding the city of Hav ...
,
Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...
. A partial left
carpometacarpus The carpometacarpus is a bone found in the hands of birds. It results from the fusion of the carpal and metacarpal bone, and is essentially a single fused bone between the wrist and the knuckles. It is a smallish bone in most birds, generally flat ...
– Specimen
AMNH The American Museum of Natural History (abbreviated as AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. In Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 26 i ...
FR 6190 – as well as a fingerbone probably date from some time in the
Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...
, during the last ice age. Its contemporary close relatives on Cuba, as far as it is known, consisted of the gigantic eagle-like buteonine hawks which were clearly distinct by size alone, while the Pleistocene record of similar-sized birds from continental North America is from the far west.
American Museum of Natural History The American Museum of Natural History (abbreviated as AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. In Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 26 inter ...
(AMNH) (2007)
AMNH FR 6190 specimen record


Ecology

The black-chested buzzard-eagle is found in mountainous or hilly
terrain Terrain or relief (also topographical relief) involves the vertical and horizontal dimensions of land surface. The term bathymetry is used to describe underwater relief, while hypsometry studies terrain relative to sea level. The Latin word ...
with sparse vegetation, shrubland or (in the south of its range) ''
Nothofagus ''Nothofagus'', also known as the southern beeches, is a genus of 43 species of trees and shrubs native to the Southern Hemisphere in southern South America (Chile, Argentina) and Australasia (east and southeast Australia, New Zealand, New Gui ...
'' forest, where it spends a lot of time
soaring Soaring may refer to: * Gliding, in which pilots fly unpowered aircraft known as gliders or sailplanes * Lift (soaring), a meteorological phenomenon used as an energy source by some aircraft and birds * ''Soaring'' (magazine), a magazine produced ...
in
thermal A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...
s and
vertical draft In meteorology, an updraft is a small-scale current of rising air, often within a cloud. Overview Localized regions of warm or cool air will exhibit vertical movement. A mass of warm air will typically be less dense than the surrounding region, ...
s while looking for
prey Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...
. It requires large territories with suitable
habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...
, the
páramo Páramo () can refer to a variety of alpine tundra ecosystems located in the Andes Mountain Range, South America. Some ecologists describe the páramo broadly as "all high, tropical, montane vegetation above the continuous timberline". A narrower ...
s at the north of its range, for example, while providing the latter, fail to provide the former, and thus it has only been recorded in the largest patches of such habitat, such as Páramo de Frontino. Most common between about and
ASL American Sign Language (ASL) is a natural language that serves as the predominant sign language of Deaf communities in the United States of America and most of Anglophone Canada. ASL is a complete and organized visual language that is express ...
, it rarely ventures into the lowlands. It is most conspicuous in the mid-morning and afternoon, when individuals will seek out places which provide the best soaring conditions, such as north and west facing slopes and ridges. Apparently, their main interest at these times is aerial play and display; they tend to ignore places where food is more plentiful or easily hunted in favor of simply soaring alone or in pairs in strong air currents. The food of this
carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...
consists mainly of mid-sized
mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s; the introduced
European rabbit The European rabbit (''Oryctolagus cuniculus'') or coney is a species of rabbit native to the Iberian Peninsula (including Spain, Portugal, and southwestern France), western France, and the northern Atlas Mountains in northwest Africa. It has ...
(''Oryctolagus cuniculus'') seems to have become a key prey item. The black-chested buzzard-eagle is helpful to farmers by keeping down the numbers of the rabbits, which can be serious agricultural pests. Among the native fauna
degus The Degus are a group of octodontid rodents in the Octodontidae family, but historically referred to the common degu (''O. degus''). Degus are placed in two genera: * Genus ''Octodon'' ** ''O. bridgesi'', Bridges's degu, found in Argentina and Chi ...
(''Octodon'') and
hog-nosed skunk The hog-nosed skunks belong to the genus ''Conepatus'' and are members of the family Mephitidae Mephitidae is a family of mammals comprising the skunks and stink badgers. They are noted for the great development of their anal scent glands, ...
s (''Conepatus'') are important prey, but mammals as formidable as a
gray fox The gray fox (''Urocyon cinereoargenteus''), or grey fox, is an omnivorous mammal of the family Canidae, widespread throughout North America and Central America. This species and its only congener, the diminutive island fox (''Urocyon littor ...
(''Urocyon cinereoargenteus'') – two to over three times as heavy as the birds and certainly not defenceless – are occasionally hunted and killed by this hawk. Its diet is rounded off with an occasional bird – including carnivorous species like the
burrowing owl The burrowing owl (''Athene cunicularia''), also called the shoco, is a small, long-legged owl found throughout open landscapes of North and South America. Burrowing owls can be found in grasslands, rangelands, agricultural areas, deserts, or an ...
(''Athene cunicularia'') and sizeable prey such as ''
Penelope Penelope ( ; Ancient Greek: Πηνελόπεια, ''Pēnelópeia'', or el, Πηνελόπη, ''Pēnelópē'') is a character in Homer's ''Odyssey.'' She was the queen of Ithaca and was the daughter of Spartan king Icarius and naiad Periboea. Pe ...
''
guan Guan may refer to: * Guan (surname), several similar Chinese surnames ** Guān, Chinese surname * Guan (state), ancient Chinese city-state * Guan (bird), any of a number of bird species of the family Cracidae, of South and Central America * Guan ( ...
s or the
Chilean tinamou The Chilean tinamou (''Nothoprocta perdicaria'') is a type of tinamou commonly found in high altitude shrubland in subtropical regions of central Chile.Clements, J (2007) Taxonomy All tinamous are from the family Tinamidae, and in the larger sch ...
(''Nothoprocta perdicaria'') –, large
squamate Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest order of reptiles, comprising lizards, snakes, and amphisbaenians (worm lizards), which are collectively known as squamates or scaled reptiles. With over 10,900 species, ...
s, and if need be also
arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...
s and
carrion Carrion () is the decaying flesh of dead animals, including human flesh. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
. While not aggressive under normal circumstances, the black-chested eagle-buzzard will fiercely attack humans if it considers itself or its offspring threatened. It is near the top of the avian food chain in its range, in part since it is the only
Andean The Andes, Andes Mountains or Andean Mountains (; ) are the List of mountain ranges#Mountain ranges by length, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range i ...
eagle found outside forest habitats. It may compete for carrion with the much larger
Andean condor The Andean condor (''Vultur gryphus'') is a giant South American Cathartid vulture and is the only member of the genus ''Vultur''. Found in the Andes mountains and adjacent Pacific coasts of western South America, the Andean condor is the larg ...
. It nests in high trees or on rocky cliffs, or if these are not available on high trees or even
cacti A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek ...
. If no appropriate high place is available this species will nest in bushes or even on the ground. In
Ecuador Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...
, nesting can be observed all year round; elsewhere it might have a more restricted breeding season but information is scant and somewhat contradictory. The nest is a huge mass of sticks about in diameter; the black-chested buzzard-eagle is just as likely to reuse an existing nest as to build a new one, and several abandoned nests are often found in the vicinity of an active one. The male and female engage in courtship flights, and
copulate Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetr ...
over a prolonged time of several weeks as the pairs bond. Little is known of the actual nesting; the
clutch A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...
contains usually 2 but sometimes 1 or 3 eggs, which are incubated for about a month. The nestlings presumably are covered in white down like in its relatives. Owing the wide overall range ''Geranoaetus melanoleucus'' is considered a Species of
Least Concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
by the
IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
. While it is rare and declining in places – e.g. in
Rio Grande do Sul Rio Grande do Sul (, , ; "Great River of the South") is a Federative units of Brazil, state in the South Region, Brazil, southern region of Brazil. It is the Federative_units_of_Brazil#List, fifth-most-populous state and the List of Brazilian st ...
and
Santa Catarina state Santa Catarina (, ) is a state in the South Region of Brazil. It is the 7th smallest state in total area and the 11th most populous. Additionally, it is the 9th largest settlement, with 295 municipalities. The state, with 3.4% of the Brazili ...
s in
Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
, or in parts of
Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
– its
habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...
requirements mean that it will to some degree benefit from
deforestation Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated d ...
and it has for example colonized regions of the former
Mata Atlântica The Atlantic Forest ( pt, Mata Atlântica) is a South American forest that extends along the Atlantic coast of Brazil from Rio Grande do Norte state in the northeast to Rio Grande do Sul state in the south and inland as far as Paraguay and the ...
forest in
Alagoas Alagoas (, ) is one of the 27 federative units of Brazil and is situated in the eastern part of the Northeast Region. It borders: Pernambuco (N and NW); Sergipe (S); Bahia (SW); and the Atlantic Ocean (E). Its capital is the city of Maceió. It ...
. The declines in Argentina have been attributed to poisoning by
strychnine Strychnine (, , US chiefly ) is a highly toxic, colorless, bitter, crystalline alkaloid used as a pesticide, particularly for killing small vertebrates such as birds and rodents. Strychnine, when inhaled, swallowed, or absorbed through the eye ...
baits deployed by sheep farmers trying to eradicate pests.


Gallery

Geranoaetus melanoleucus Santiago 01.jpg, Geranoaetus melanoleucus Geranoaetus melanoleucus EM1B1863 (47485600011).jpg, Captive Geranoaetus melanoleucus at Palmitos Park, Canary Islands, Spain Geranoaetus melanoleucus EM1B1865 (47485599851).jpg, Captive Geranoaetus melanoleucus at Palmitos Park, Canary Islands, Spain Geranoaetus melanoleucus EM1B2151 (40519631623).jpg, Captive Geranoaetus melanoleucus in a high speed dive at Palmitos Park, Canary Islands, Spain


References

{{Taxonbar, from=Q633877 Buteoninae Hawks Eagles Birds of South America Birds described in 1819 Taxa named by Louis Jean Pierre Vieillot