Eagle is the common name for many large
birds 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 ...
of the family
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 ...
. Eagles belong to several groups of
genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just 14 species can be found—2 in North America, 9 in Central and South America, and 3 in Australia.
Eagles are not a natural group but denote essentially any kind of
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 ...
large enough to hunt sizeable (about 50 cm long or more overall)
vertebrates
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
.
Description
Eagles are large, powerfully-built
birds 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 ...
, with heavy heads and beaks. Even the smallest eagles, such as the
booted eagle
The booted eagle (''Hieraaetus pennatus'', also classified as ''Aquila pennata'') is a medium-sized mostly migratory bird of prey with a wide distribution in the Palearctic and southern Asia, wintering in the tropics of Africa and Asia, with a ...
(''Aquila pennata''), which is comparable in size to a
common buzzard
The common buzzard (''Buteo buteo'') is a medium-to-large bird of prey which has a large range. A member of the genus ''Buteo'', it is a member of the family Accipitridae. The species lives in most of Europe and extends its breeding range across ...
(''Buteo buteo'') or
red-tailed hawk
The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members with ...
(''B. jamaicensis''), have relatively longer and more evenly broad wings, and more direct, faster flight – despite the reduced size of aerodynamic feathers. Most eagles are larger than any other raptors apart from some
vulture
A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture (including Condors). Old World vultures include 16 living species native to Europe, Africa, and Asia; New World vultures are restricted to North and ...
s. The smallest species of eagle is the
South Nicobar serpent eagle
The Great Nicobar serpent eagle (''Spilornis klossi''), also known as the South Nicobar serpent eagle, is a species of bird of prey in the family Accipitridae. It is probably the smallest known eagle, with a weight of about , a wingspan of and a ...
(''Spilornis klossi''), at and . The largest species are discussed below. Like all birds of prey, eagles have very large hooked
beak
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 ...
s for ripping flesh from their prey, strong, muscular legs, and powerful
talons
A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or tarsus ...
.
The beak is typically heavier than that of most other birds of prey. Eagles' eyes are extremely powerful. It is estimated that the
martial eagle
The martial eagle (''Polemaetus bellicosus'') is a large eagle native to sub-Saharan Africa.Ferguson-Lees & Christie, ''Raptors of the World''. Houghton Mifflin Company (2001), . It is the only member of the genus ''Polemaetus''. A species of t ...
, whose eyes are more than two times larger than the human eye, has a
visual acuity
Visual acuity (VA) commonly refers to the clarity of vision, but technically rates an examinee's ability to recognize small details with precision. Visual acuity is dependent on optical and neural factors, i.e. (1) the sharpness of the retinal ...
up to 8 times that of humans. This acuity enables eagles to spot potential prey from a very long distance. This keen eyesight is primarily attributed to their extremely large pupils which ensure minimal
diffraction
Diffraction is defined as the interference or bending of waves around the corners of an obstacle or through an aperture into the region of geometrical shadow of the obstacle/aperture. The diffracting object or aperture effectively becomes a s ...
(scattering) of the incoming light. The female of all known species of eagles is larger than the male.
Eagles normally build their nests, called
eyries, in tall trees or on high cliffs. Many species lay two eggs, but the older, larger chick frequently kills its younger sibling once it has hatched. The parents take no action to stop the killing.
It is said that eagles fly above clouds but this is not true. Eagles fly during storms and glide from the winds pressure. This saves the bird's energy.
Due to the size and power of many eagle species, they are ranked at the top of the food chain as
apex predator
An apex predator, also known as a top predator, is a predator at the top of a food chain, without natural predators of its own.
Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic lev ...
s in the avian world. The type of prey varies by genus. The ''
Haliaeetus
A sea eagle or fish eagle (also called erne or ern, mostly in reference to the white-tailed eagle) is any of the birds of prey in the genus ''Haliaeetus'' in the bird of prey family Accipitridae.
Taxonomy and evolution
The genus ''Haliaeetus'' ...
'' and ''
Ichthyophaga
A sea eagle or fish eagle (also called erne or ern, mostly in reference to the white-tailed eagle) is any of the birds of prey in the genus ''Haliaeetus'' in the bird of prey family Accipitridae.
Taxonomy and evolution
The genus ''Haliaeetus'' ...
'' eagles prefer to capture fish, though the species in the former often capture various animals, especially other
water bird
A water bird, alternatively waterbird or aquatic bird, is a bird that lives on or around water. In some definitions, the term ''water bird'' is especially applied to birds in freshwater ecosystems, although others make no distinction from seabi ...
s, and are powerful
kleptoparasites of other birds. The snake and serpent eagles of the genera ''
Circaetus
''Circaetus'', the snake eagles, is a genus of medium-sized eagles in the bird of prey family Accipitridae. They are mainly resident African species, but the migratory short-toed snake eagle breeds from the Mediterranean basin into Russia, the M ...
'', ''
Terathopius
The bateleur (; ''Terathopius ecaudatus'') is a medium-sized eagle in the family Accipitridae. It is often considered a relative of the snake eagles and, like them, it is classified within the subfamily Circaetinae.Kemp, A. C., G. M. Kirwan, an ...
'', and ''
Spilornis
''Spilornis'' is a genus of bird of prey in the family Accipitridae. As adults all have dark crowns, and bright yellow eyes and cere.Ferguson-Lees & Christie (2001). ''Raptors of the World.'' Christopher Helm, London. These medium-sized raptors ...
'' predominantly prey on the great diversity of
snake
Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...
s found in the tropics of Africa and Asia. The eagles of the genus ''
Aquila'' are often the top birds of prey in open habitats, taking almost any medium-sized
vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
they can catch. Where ''Aquila'' eagles are absent, other eagles, such as the
buteonine black-chested buzzard-eagle
The black-chested buzzard-eagle (''Geranoaetus melanoleucus'') is a bird of prey of the hawk and eagle family (Accipitridae). It lives in open regions of South America. This species is also known as the black buzzard-eagle, the gray buzzard-eag ...
of South America, may assume the position of top raptorial predator in open areas. Many other eagles, including the species-rich genus ''
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 ...
'', live predominantly in woodlands and forests. These eagles often target various arboreal or ground-dwelling mammals and birds, which are often unsuspectingly ambushed in such dense, knotty environments. Hunting techniques differ among the species and genera, with some individual eagles having engaged in quite varied techniques based on their environment and prey at any given time. Most eagles grab prey without landing and take flight with it, so the prey can be carried to a perch and torn apart.
The
bald eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as ...
is noted for having flown with the heaviest load verified to be carried by any flying bird, since one eagle flew with a
mule deer
The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer.
Unlike the related whit ...
fawn. However, a few eagles may target prey considerably heavier than themselves; such prey is too heavy to fly with, thus it is either eaten at the site of the kill or taken in pieces back to a perch or nest.
Golden
Golden means made of, or relating to gold.
Golden may also refer to:
Places United Kingdom
*Golden, in the parish of Probus, Cornwall
* Golden Cap, Dorset
*Golden Square, Soho, London
*Golden Valley, a valley on the River Frome in Gloucestershi ...
and
crowned eagle
The crowned eagle, also known as the African crowned eagle or the crowned hawk-eagle (''Stephanoaetus coronatus''), is a large bird of prey found in sub-Saharan Africa; in Southern Africa it is restricted to eastern areas.Sinclair & Ryan (2003) ...
s have killed
ungulate
Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...
s weighing up to and a
martial eagle
The martial eagle (''Polemaetus bellicosus'') is a large eagle native to sub-Saharan Africa.Ferguson-Lees & Christie, ''Raptors of the World''. Houghton Mifflin Company (2001), . It is the only member of the genus ''Polemaetus''. A species of t ...
even killed a
duiker
A duiker is a small to medium-sized brown antelope native to sub-Saharan Africa, found in heavily wooded areas. The 22 extant species, including three sometimes considered to be subspecies of the other species, form the subfamily Cephalophina ...
, 7–8 times heavier than the preying eagle.
Authors on birds David Allen Sibley
David Allen Sibley (born October 22, 1961, in Plattsburgh, New York) is an American ornithologist. He is the author and illustrator of ''The Sibley Guide to Birds'', which rivals Roger Tory Peterson's as the most comprehensive guides for Nort ...
, Pete Dunne
Peter Thomas England (born 9 November 1993) is an English professional wrestler. He is currently signed to WWE, where he performs on the SmackDown brand under the ring name Butch. He is a former WWE United Kingdom Champion and also a former NXT ...
, and Clay Sutton described the behavioral difference between hunting eagles and other birds of prey thus (in this case the bald and golden eagles as compared to other North American raptors):
They have at least one singular characteristic. It has been observed that most birds of prey look back over their shoulders before striking prey (or shortly thereafter); predation is after all a two-edged sword. All hawks seem to have this habit, from the smallest kestrel to the largest Ferruginous – but not the Eagles.
Among the eagles are some of the largest birds of prey: only the