Fact-checked by Grok 2 weeks ago

Spizaetus

Spizaetus is a of four of hawk-eagles in the family , endemic to the Neotropical region from central south to northern . These medium- to large-sized raptors are distinguished by their hawk-like proportions, including shorter wings relative to their long tails, tall thin tarsi, and weaker talons compared to typical , along with prominent crests on their heads. The genus name derives from the Greek words spizias () and aetos (), reflecting their intermediate between hawks and eagles. The four extant species are the (S. tyrannus), ornate hawk-eagle (S. ornatus), (S. melanoleucus), and (S. isidori). Phylogenetic analyses using mitochondrial and nuclear DNA have confirmed that these species form a monophyletic , with S. tyrannus as the basal member and the other three more closely related to each other. Historically, S. melanoleucus was placed in the monotypic Spizastur and S. isidori in Oroaetus due to morphological differences, but molecular evidence has supported their inclusion in Spizaetus. Formerly, the genus also included several species now reclassified in Nisaetus based on . These hawk-eagles inhabit tropical and subtropical forests, typically at low to mid-elevations, where they perch in the canopy and hunt by soaring or making short flights. Their consists primarily of , mammals, and reptiles, captured through agile aerial pursuits or from perches. The and black-and-white hawk-eagle are classified as Least Concern, the as Near Threatened, and the black-and-chestnut eagle as Endangered by the IUCN (as of 2024), though habitat loss poses ongoing threats across their range.

Taxonomy

Etymology

The genus name Spizaetus was coined by French ornithologist Louis Jean Pierre Vieillot in 1816, in his work Analyse d'une nouvelle ornithologie élémentaire, with the (Falco ornatus Vieillot, 1816, now Spizaetus ornatus) as the . This establishment marked one of the early applications of systematic -level classification for Neotropical raptors within the family. Etymologically, Spizaetus combines the Ancient Greek σπιζίας (spizías), denoting a sparrowhawk or small hawk such as Accipiter nisus, with ἀετός (aetós), meaning "eagle." The construction reflects perceptions of these birds as intermediate in form and behavior between compact hawks and larger eagles, possibly stemming from observations of their agile flight and predation on small to medium-sized vertebrates, which evoked hawk-like traits in an eagle-sized body. The introduction of Spizaetus occurred amid the consolidation of in during the early 19th century, following Carl Linnaeus's foundational (1758), which standardized two-part Latin naming to catalog global biodiversity as European exploration expanded knowledge of tropical avifauna. By this era, ornithologists employed such nomenclature to resolve taxonomic ambiguities in descriptions derived from museum specimens and field reports, fostering a more rigorous, international framework for avian systematics.

Classification history

The genus Spizaetus was established by French ornithologist Louis Jean Pierre Vieillot in 1816, with the (Spizaetus ornatus) designated as the . This initial description placed the genus within the family , encompassing tropical hawk-eagles primarily from the . In the late 20th and early 21st centuries, phylogenetic studies using revealed that the traditional Spizaetus was paraphyletic, leading to significant taxonomic revisions. species, such as the (Nisaetus cirrhatus), were reassigned to the revived genus Nisaetus based on genetic evidence showing distinct evolutionary lineages separate from taxa; this reassignment was proposed in analyses published around 2005–2007. Concurrently, the monotypic genera Spizastur (black-and-white hawk-eagle, S. melanoleucus) and Oroaetus (, S. isidori) were merged into Spizaetus based on molecular and morphological data indicating close relatedness and of the species; these changes were adopted by the South American Classification Committee in 2007 and by the American Ornithologists' Union for North American taxa. Current classification positions Spizaetus within the subfamily (booted eagles) of , with four recognized species forming a monophyletic New World clade. Phylogenetic analyses confirm Spizaetus as sister to a broader group excluding certain basal lineages like Stephanoaetus, highlighting convergent evolution in hawk-eagle across continents.

Description

Morphology

Spizaetus species are medium to large raptors, with body lengths ranging from 55 to 77 cm and wingspans from 110 to 172 cm across the genus. Weights vary from approximately 900 g to 3,500 g, with females typically larger than males in all species. These eagles exhibit a slender build adapted for agile flight through forested environments, featuring broad, paddle-shaped wings and a relatively long, rounded tail that can constitute up to 40% of total body length. Their legs, or tarsi, are fully feathered down to the toes, providing and in arboreal habitats. A defining feature is the prominent occipital on the head, composed of 2–4 elongated feathers measuring 5–10 cm in length, which can be raised or lowered. This serves functions in , often erected during excitement or agitation to signal mood or intimidate. The bill is strongly hooked and ceres-covered, typical of accipitrids, enabling efficient tearing of prey flesh. Talons are sharp, curved, and powerful, adapted for grasping and subduing arboreal mammals, birds, and reptiles during predation.

Plumage variations

Species in the genus Spizaetus are characterized by dark brown to blackish upperparts, which provide effective against the canopy, and underparts that are typically barred or mottled in shades of white, , or , varying by . For instance, the (S. tyrannus) displays blackish overall with narrow white barring on the underparts and broad white bars on the , while the (S. ornatus) features rich sides of the neck and heavily barred underparts. A prominent occipital of elongated feathers is a defining feature across the , often held erect or laid flat depending on the bird's of alertness; in some , such as the Black-and-white Hawk-Eagle (S. melanoleucus), the crest feathers are black with white tips. Sexual dimorphism in body size is present in Spizaetus, with females larger than males—a pattern (reverse sexual dimorphism) typical of accipitrid raptors that may relate to differential foraging roles or fecundity advantages. differences between sexes are subtle but present, particularly in barring intensity; for example, adult female Black-and-white Hawk-Eagles exhibit more pronounced blackish barring on the wings compared to males, while overall patterns remain similar across sexes in species like the . The crest plays a role in visual signaling, often raised during moments of excitement, alarm, or displays to convey or reproductive intent, as observed in the where it can be erected to emphasize the bird's presence. Juvenile plumage in Spizaetus species is markedly paler and less distinctly marked than that of adults, facilitating among foliage and reducing visibility to predators during the vulnerable fledging period. In the Black Hawk-Eagle, juveniles appear largely buffy white with black mottling and streaking on the head and breast, contrasting the adults' darker, more uniform tones. Similarly, young Black-and-chestnut Eagles (S. isidori) are nearly white below with gray-brown upperparts and barred , a pattern that blends with light understories; this ontogenetic shift to adult coloration occurs through successive molts, enhancing hunting efficacy as the birds mature. In the , juveniles have unmarked white head and upperparts initially, gradually developing the bold rufous and barred patterns of adults.

Distribution and habitat

Geographic range

The genus Spizaetus, comprising Neotropical hawk-eagles, is distributed across the from central southward through and into northern , extending to northern and . This range encompasses a broad swath of tropical and subtropical regions, with the core distribution centered in the humid forests of and the , as well as the Andean foothills. Populations exhibit disjunct patterns, particularly in highland areas east and west of the , where suitable forest habitats are fragmented, leading to isolated occurrences in countries such as , , , , and . The genus occupies elevations primarily from to 2,500 m, though some species, like the black-and-chestnut hawk-eagle (S. isidori), are recorded up to 3,500 m in montane zones. Historical records indicate range contractions due to , with observational data showing declines in formerly occupied areas, such as parts of eastern and the Pacific lowlands of and , including estimated population reductions of 20–29% over the past three generations (as of 2023) for species like S. ornatus and S. isidori, based on surveys and data. These changes are documented through long-term surveys and tracking loss, highlighting the genus's vulnerability to fragmentation without evidence of significant historical expansions.

Habitat requirements

Species of the genus Spizaetus, commonly known as hawk-eagles, primarily occupy tropical and subtropical moist , encompassing both primary undisturbed woodlands and areas that retain sufficient canopy cover. These raptors thrive in environments with dense vegetation that supports their arboreal hunting strategies and nesting behaviors, such as humid and forests. While some , like the (S. tyrannus), tolerate forest edges and moderately disturbed landscapes, the genus as a whole depends on forested ecosystems for cover and prey availability. Many Spizaetus species exhibit specialization in or montane forests, particularly cloud forests at elevations ranging from 1,000 to 3,500 m, where and epiphyte-laden trees create ideal conditions for perching and ambushing prey. For instance, the (S. isidori) is restricted to Andean montane cloud forests, avoiding lower, drier s. Across the genus, open savannas, grasslands, and urbanized areas are unsuitable due to the lack of structural complexity and vulnerability to predation or disturbance in exposed settings. Nesting requirements are stringent, with Spizaetus pairs constructing large stick platforms in the upper canopy of tall emergent trees, typically 20–40 m in height and with substantial girth ( often exceeding 50 cm). These sites are selected for their isolation and overlook of the surrounding forest, providing protection from ground predators and optimal vantage points; preferred tree genera include , , and . Such elevated, mature structures are scarce in degraded or young secondary forests, underscoring the genus's reliance on old-growth elements. Spizaetus species are highly sensitive to , as their large home ranges (typically 10–20 km² per pair for some species) necessitate contiguous forest blocks to maintain viable populations and . Fragmented patches smaller than this threshold fail to support breeding pairs, leading to isolation and elevated risks, as observed in Neotropical populations. Recent analyses indicate tree cover loss of 7–14% over the past three generations (2000–2022) across key habitats, per Global Forest Watch data. Conservation efforts thus prioritize protecting extensive, unbroken forest tracts to mitigate these pressures.

Behavior and ecology

Diet and hunting

Species in the genus Spizaetus are obligate carnivores that primarily consume medium-sized arboreal vertebrates, including mammals such as squirrels, opossums, coatis, and small monkeys; birds like guans, toucans, and macaws; and reptiles such as iguanas and snakes. In studies of the black hawk-eagle (S. tyrannus), arboreal mammals comprised 95.3% of the diet at one site, with birds making up the remainder and reptiles taken less frequently. For the ornate hawk-eagle (S. ornatus), records document 78 bird species (primarily galliforms like guans), 38 mammal species (mostly rodents and primates), and a few reptiles, highlighting a diverse but forest-adapted prey base. Prey selection favors individuals weighing 200–1,000 g, though smaller items around 50 g (e.g., bats) and larger ones up to 3.5 kg (e.g., macaws) are occasionally taken; for instance, 91% of observed prey for S. tyrannus weighed 200 g or less. Opportunistic scavenging is rare, limited to isolated observations such as S. tyrannus consuming remnants from feces or carrion. Hunting strategies emphasize canopy-level predation in tropical forests, often involving sit-and-wait tactics from concealed perches where the eagle scans for movement before swooping with wings outstretched and talons extended. Soaring flight over the forest canopy or adjacent clearings allows for spotting prey, followed by abrupt, high-speed dives into dense vegetation to capture arboreal targets in flight or on branches; the black-and-white hawk-eagle (S. melanoleucus) relies on this aerial method for over 90% bird prey. Ambushes target resting or sleeping mammals, with short tail-chasing pursuits through foliage also documented in S. ornatus. These techniques leverage the eagles' powerful flight and physical adaptations, such as robust talons, for seizing elusive forest prey. Dietary composition shows some flexibility with prey availability, though specific seasonal shifts remain understudied; in forested habitats, reliance on arboreal persists year-round due to stable canopy resources.

Reproduction and nesting

Species of the genus Spizaetus typically form monogamous pairs that maintain long-term bonds for . These pairs engage in displays, including aerial chases and vocalizations, to reinforce their partnership before nesting. Breeding occurs seasonally in most populations, often initiating during the and extending into the transition to the , which aligns with prey availability in tropical forests. For instance, in the (S. isidori), nesting activity peaks from February to August in , corresponding to drier months. Similarly, the (S. ornatus) breeds from March to July in , a period marking the onset of rains. Near the equator, such as in parts of for the (S. tyrannus), breeding can be more aseasonal but still shows peaks from December to March. Clutch sizes are typically one , though rare instances of two have been recorded, as in the Black Hawk-Eagle in . Eggs are white with brown spots and laid in a single brood per season. Incubation lasts 35–51 days, depending on the , with the female performing the majority of duties—often over 95% of the time—while the male provides food and occasionally relieves her briefly. Nests are constructed as large platforms of sticks, measuring 1–1.5 m in and 0.5–1 m deep, typically placed high in the canopy (20–40 m) of mature forest trees, often in tangles or emergent for . These structures are lined with fresh green leaves or sprigs, which may be renewed periodically to maintain and signaling. Pairs often reuse and expand the same nest site annually or over multiple years if successful, as documented in the Hawk-Eagle (S. melanoleucus) and . The fledging period varies from 60–70 days in the Black-and-white Hawk-Eagle to about 87–91 days in the Ornate and Black-and-chestnut Eagles, after which juveniles remain dependent on parents for several months to a year. Chick mortality is high, primarily due to predation; for example, juveniles have been lost to predators at 5.7 and 8 months post-hatching, contributing to overall low reproductive success in the genus. Nests are often built in forested habitats with dense cover to mitigate such risks.

Species

Current species

The genus Spizaetus currently comprises four extant , all endemic to the Neotropics and classified as hawk-eagles within the family . These are characterized by their forest-dwelling habits and crested heads, with varying degrees of contrast that aid in identification. The (S. tyrannus) is the most widespread, ranging from central through to northern , including countries such as , , and , with an extent of occurrence of 17,500,000 km². It is distinguished by its bold black crest with white bases, silky black overall , and narrow white bars on the undertail and underwings. Classified as Least Concern by the IUCN, its global population is estimated to be stable in size but declining due to habitat loss and , with a global population estimate of 50,000–499,999 mature individuals (as of 2016) that is undergoing a moderate decline, though it remains common in suitable forests. The black-and-white hawk-eagle (S. melanoleucus) occupies humid forests from southern southward to northern , spanning an extent of occurrence of 18,100,000 km² across Central and . Its striking white underparts, including the head, neck, and body, contrast sharply with black upperparts, wings, and a small forming a black spot on the head; in flight, it shows a leading edge on the inner wing. IUCN status is Least Concern, with a global population of 20,000–49,999 mature individuals that is decreasing owing to . The (S. ornatus) is found in tropical forests from southeast through to northern , extending south to eastern , , and northern , with an extent of occurrence of 20,500,000 km². Key traits include intricate black barring on the white underparts, a long erectile nuchal crest that can be raised, and sides to the neck and chest. It is listed as Near Threatened by the IUCN, with a of 50,000–499,999 individuals (as of 2016) projected to decline by 20–29% over the next three generations (25.9 years) primarily due to habitat loss in the and hunting pressure. The (S. isidori), the largest in the , inhabits montane forests along the from coastal through , , and to west-central and northwestern , with a narrower extent of occurrence of 4,680,000 km² at elevations of 1,500–2,800 m. It features prominent chestnut patches on the breast, belly, and tarsi against otherwise black , along with a dark crest and white patches in the primaries and tail base. Classified as Endangered by the IUCN, its small population (estimated at 1,400–4,200 mature individuals as of 2023) is decreasing due to and .

Former members

The genus Spizaetus historically included both and hawk-eagles, but molecular phylogenetic studies demonstrated its , prompting the transfer of species to the resurrected genus Nisaetus in 2005. This separation was driven by analyses of sequences, including the control region and cytochrome b gene, which revealed deep genetic divergences between and lineages, with taxa forming a monophyletic distinct from the Neotropical species. Key former members reassigned to Nisaetus include the mountain hawk-eagle (N. nipalensis), previously Spizaetus nipalensis, which inhabits montane forests from the to ; Blyth's hawk-eagle (N. alboniger), endemic to the and ; and the (N. philippensis), restricted to the . Other examples encompass the (N. bartelsi), Sulawesi hawk-eagle (N. lanceolatus), and (N. cirrhatus), all of which were lumped under Spizaetus due to superficial morphological similarities like crested heads and hawk-like flight, but diverged evolutionarily during the . These shifts were further supported by subsequent studies confirming in plumage and ecology between the lineages. The reclassification has significant conservation implications, as it enables species-specific evaluations under frameworks like the , leading to tailored protections for taxa facing threats such as and illegal trade. For instance, endemic species like the now receive focused regional safeguards in biodiversity hotspots, distinct from conservation priorities, thereby enhancing overall raptor management in .

References

  1. [1]
    Include Oroaetus isidori and Spizastur melanoleucus in Spizaetus
    The Black Hawk-Eagle (Spizaetus tyrannus) is “basal” to the entire clade. The Old World "Spizaetus" are not sister to the New World Spizaetus (S. ornatus ...
  2. [2]
    Systematics - Black-and-white Hawk-Eagle - Spizaetus melanoleucus
    Aug 15, 2025 · The genus name Spizaetus comes from the Greek Spizias, for hawk, and Aëtos, for eagle (34 Jobling, J. A. (2010). The Helm Dictionary of ...
  3. [3]
    Black Hawk-Eagle Spizaetus tyrannus - Birds of the World
    Jun 13, 2025 · The Black Hawk-Eagle has blackish plumage with white barring, broad paddle-shaped wings, a long tail, and feeds on mammals, birds, and reptiles ...
  4. [4]
    Ornate Hawk-Eagle Spizaetus ornatus - Birds of the World
    The Ornate Hawk-Eagle has a broad range throughout much of the Neotropics, living in tropical forests generally below 1800 meters.
  5. [5]
    Ornate Hawk-eagle Spizaetus Ornatus Species Factsheet
    Ornate Hawk-eagle. Spizaetus ornatus. Accipitridae (Hawks, Eagles). Number of mature individuals. 50,000 - 499,999. Population trend. Decreasing. NT. IUCN Red ...
  6. [6]
    Case Studies of Birds of Prey (Spizaetus taxon) | IntechOpen
    The first description of the genus Spizaetus was introduced by Vieillot in 1816, when he described the taxon S. ornatus (Haring et al. 2007). This species ...Missing: etymology origin
  7. [7]
    [PDF] Helm Dictionary of Scientific Bird Names
    This new Dictionary owes much to R. D. Macleod's Key to the Names of British Birds. (1954) and to my well-received A Dictionary of Scientific Bird Names (1991).
  8. [8]
    Reinforcing the foundations of ornithological nomenclature - ZooKeys
    Jan 7, 2016 · Linnaeus (1758 , 1766 ) provided the starting point, and the elaborated rules for scientific nomenclature meant that the content of the ...
  9. [9]
    Convergent evolution and paraphyly of the hawk‐eagles of the ...
    May 25, 2007 · Therefore, we suggest assigning the species of the genus Spizaetus to three different genera: (1) Spizaetus (including Oroaetus isidori) in ...Missing: reassignment | Show results with:reassignment
  10. [10]
    [PDF] FORTY-EIGHTH SUPPLEMENT TO THE AMERICAN ...
    Genetic studies (Helbig et al. 2005) indicate that the genus Spizastur should be merged into Spizaetus, and that the species mela- noleucus is closely related ...
  11. [11]
    [PDF] Phylogeny and new taxonomy of the Booted Eagles (Accipitriformes
    Jan 9, 2017 · We find molecular support for five major clades within the booted eagles: Nisaetus (10 species), Spizaetus (4 species), Clanga (3 species), ...
  12. [12]
    Field Identification - Black Hawk-Eagle - Spizaetus tyrannus
    Jun 13, 2025 · A medium to large dark raptor with a black body, black-and-white feathered tarsi, broadly black-and-white banded flight feathers, ...
  13. [13]
    Field Identification - Ornate Hawk-Eagle - Spizaetus ornatus
    Immature Black-and-chestnut Eagle (Spizaetus isidori) is somewhat similar in size and shape, and is also crested, but has a head washed with brownish, unbarred ...
  14. [14]
    Black-and-chestnut Eagle - Spizaetus isidori - Birds of the World
    Apr 19, 2024 · It is recognized by its large size (63–77 cm length, 147–172 cm wingspan, and up to 3,500 g weight), as well as its distinct plumage pattern. In ...
  15. [15]
  16. [16]
    Ornate Hawk-Eagle - American Bird Conservancy
    This extraordinary raptor also has a crest of long black feathers, which the bird may keep flattened or held erect when excited. The birds are often seen ...Missing: function camouflage
  17. [17]
    Black-and-white Hawk-Eagle - Spizaetus melanoleucus
    Aug 15, 2025 · The Black-and-white Hawk-Eagle is an elegant forest raptor with a wide distribution across the Neotropics, ranging from central Mexico to ...
  18. [18]
    Sex affects the nestling diet of a large aerial predator of the Andes
    Jul 9, 2025 · The phenomenon of reversed sexual dimorphism—where females are larger than males—in raptors occurs either because large females are better ...
  19. [19]
    Ornate Hawk-eagle | The Peregrine Fund
    The long black feathers on top of an Ornate Hawk-eagle's head is called a crest, which can be lowered and raised at will. A raised crest can mean the bird ...
  20. [20]
    Plumages, Molts, and Structure - Ornate Hawk-Eagle
    Mar 4, 2020 · Tail boldly banded with broad black and gray-brown bands with pale grayish tip. Underwings whitish, contrasting strongly with dark body.
  21. [21]
    Distribution - Ornate Hawk-Eagle - Spizaetus ornatus
    Mar 4, 2020 · An inhabitant of tropical forest, primarily below 1800 m, Ornate Hawk-Eagle has a broad range throughout much of the Neotropics.<|control11|><|separator|>
  22. [22]
    [PDF] SPIZAETUS - The Peregrine Fund
    Jun 23, 2017 · Although the Harpy Eagle has historically been reported up to 2000 m above sea level on the Caribbean side of Costa Rica, throughout its.
  23. [23]
    (PDF) Deforestation May Trigger Black-and-Chestnut Eagle ...
    Oct 31, 2025 · All species experienced more than 30% shrinkage in their historical distribution (before the year 2000). ... due to changes in populations of ...
  24. [24]
    Habitat - Black Hawk-Eagle - Spizaetus tyrannus - Birds of the World
    Jun 13, 2025 · General Habitat. The Black Hawk-Eagle inhabits generally lowlands in tropical forests, but in some regions can reach above 2,000 m.
  25. [25]
    Habitat - Ornate Hawk-Eagle - Spizaetus ornatus - Birds of the World
    Primarily a bird of lowland forest and tall gallery forest. In Mexico, it occurs in tropical rainforest and deciduous forests, cloud forests, ...
  26. [26]
    A comprehensive review of the endangered Black-and-chestnut ...
    Nov 24, 2022 · The Black-and-chestnut Eagle (Spizaetus isidori) is a large apex predator (63–74 cm; 2–3.5 kg) endemic to South American montane cloud forest.
  27. [27]
    Habitat - Black-and-white Hawk-Eagle - Spizaetus melanoleucus
    Aug 15, 2025 · The Black-and-white Hawk-Eagle prefers lowland forests, mainly between sea level and 1,000 m, but locally it can go up to 2,900 m in some ...
  28. [28]
    BREEDING ECOLOGY, NESTING HABITAT AND THREATS TO A ...
    Jun 29, 2023 · The Black-and-chestnut Eagle Spizaetus isidori is an endangered and little-known top predator of South American montane forests.
  29. [29]
    Breeding - Black Hawk-Eagle - Spizaetus tyrannus - Birds of the World
    Jun 13, 2025 · Site Characteristics. In Mexico, a nest was found in a 23 m tall mahogany tree (Swieteni amacrophylla) with a diameter at breast high of 1.94 m ...
  30. [30]
    Forest fragmentation and the conservation of raptors: A survey on ...
    The two forest hawk eagles (S. bartelsi and Hieraaetus kienerii) may have minimum home range sizes of about 20–30 km2 and may not survive in forest patches ...
  31. [31]
    Breeding biology and conservation of hawk-eagles (Spizaetus spp ...
    Neotropical hawk-eagles (Spizaetus spp.) are large forest raptors, having low population densities and high sensitivity to human disturbance.
  32. [32]
    Diet and Foraging - Black Hawk-Eagle - Spizaetus tyrannus
    Jun 13, 2025 · Usually takes arboreal mammals (at least 16 species), reptiles (at least 4 species) and medium-sized birds (at least 7 species). Common prey ...
  33. [33]
    (PDF) Diet of Ornate Hawk-Eagle (Spizaetus ornatus) - ResearchGate
    Aug 7, 2025 · It hunts birds, mammals and reptiles, picking up both on the ground and on the branches in the forest. Here we report data on a pair and one ...Missing: techniques | Show results with:techniques
  34. [34]
    Ornate Hawk Eagle - Spizaetus ornatus | The Eagle Directory
    The tail is black with four or five thin bands of gray and a white tip and ... Size: Length: 58-67 cm. Wingspan: 90-120 cm. Weight: Male: 964 g-1.0 kg ...
  35. [35]
    Diet and Foraging - Black-and-white Hawk-Eagle - Birds of the World
    Aug 15, 2025 · Among all Spizaetus eagles, it is the most ornithophagous, demonstrating a marked preference for avian prey. Feeding. Microhabitat for Foraging.<|control11|><|separator|>
  36. [36]
  37. [37]
  38. [38]
  39. [39]
    Demography and Populations - Black Hawk-Eagle - Birds of the World
    Jun 13, 2025 · Causes of Mortality. Human persecution (firearms) in retaliation of poultry predation have been detected in many countries and is believed to ...
  40. [40]
    Black Hawk-eagle Spizaetus Tyrannus Species Factsheet
    This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion.
  41. [41]
    Plumages, Molts, and Structure - Black Hawk-Eagle
    Jun 13, 2025 · The Definitive Basic Plumage is silky black overall. Feathers of occipital crest black, with white bases. Feathered tarsi and thighs narrowly ...
  42. [42]
    Black Hawk-eagle | The Peregrine Fund
    The Black Hawk-eagle is also known as Tyrant Hawk-eagle. There are three other hawk-eagle species in the Spizaetus genus - and all are found in the Americas.
  43. [43]
    Black-and-white Hawk-eagle Spizaetus Melanoleucus Species ...
    Taxonomy. Order. Accipitriformes. Family. Accipitridae. Authority. (Vieillot, 1816). Taxonomic sources. del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A.Missing: genus | Show results with:genus<|control11|><|separator|>
  44. [44]
    Black and White Hawk-Eagle - Birds of Colombia
    As its name suggests, it has a predominantly black and white plumage. The head, neck, and underparts are white, while the back, wings, and tail are black. It ...
  45. [45]
    Black-and-white Hawk-eagle | The Peregrine Fund
    The Black-and-white Hawk-eagle is a Neotropical bird of prey, found from southern Mexico to eastern Peru, through Brazil and northern Argentina.
  46. [46]
    Ornate Hawk-Eagle (Spizaetus ornatus) - Planet of Birds
    Aug 27, 2011 · The genus Spizaetus is a genus of ten species. It is a tropical genus of forest eagles, closely related to a couple of other genera of ...
  47. [47]
    Ornate Hawk-eagle (Spizaetus ornatus) - World Land Trust
    The Ornate Hawk-eagle's range covers most of the Neotropics – with a fairly consistent range from southern Mexico to Panama. ... The species' primary habitat ...
  48. [48]
    Black-and-chestnut Eagle Spizaetus Isidori Species Factsheet
    Nests are placed in tall trees in dense forest (Rivas-Fuenzalida et al. 2022). The breeding period usually spans the dry season, but may vary geographically ...
  49. [49]
    Black-and-chestnut Eagle | The Peregrine Fund
    The Black-and-chestnut Eagle builds huge nest structures composed of sticks and twigs. It makes its nest high in a tall tree - usually one emerging from the top ...
  50. [50]
    [PDF] Molecular phylogeny of the hawk-eagles (genus Spizaetus)
    Gamauf, A, J.O. Gjershaug, K. Kvaløy, N. Røv & E. Haring, Molecular phylogeny of the hawk-eagles. (genus Spizaetus). Zool. Med. Leiden 79-3 (21), 30-ix-2005 ...
  51. [51]
    [PDF] Taxonomy and conservation status of hawk-eagles (genus Nisaetus ...
    This name is used instead of Spizaetus because the latter genus is polyphyletic with clades in Asia, South America and Africa. The Changeable Hawk-eagle complex ...