Crested Eagle (Morphnus guianensis)

Crested Eagle

[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Morphnus guianensis | [authority] Daudin, 1800 | [UK] Crested Eagle | [FR] Harpie huppee | [DE] Wurgadler | [ES] Arpia Menor | [NL] Wurgarend

Subspecies

Monotypic species

Genus

Members of the genus Morphnus are large eagles with rounded wings, and very long and broad secondaries. The tail is also very long. The legs are not feathered. They have a long occipital crest. The plumage of the adult is highly variable in colour. They are closely related to the Harpy Eagle, but are more slender, the legs and feet are weaker, and the crest is not divided. There is but one species, resident in the tropical lowlands of the New World.

Physical charateristics

The adult Guiana Crested Eagle in normal phase has a greyish black crown, becoming more grey on the sides of the head and neck. The feathers, with the exception of the longest ones that form the crest, are narrowly tipped with greyish white. The mantle is black or brownish black; the upper-wing coverts, lower back and tail coverts are tipped with white. The tail is black with three narrow bands of grey and white and a pale tip. The throat and breast are brownish grey, paler on the throat with some black encroaching on the sides of the neck. The rest of the under surface, including the wing linings, is white or off-white, lightly barred with dark brown. The primaries are barred with black and marbled grey; the bars being darker and less noticeable on the upper surface of the wing. Females tend to be a little darker on the head and breast than are the males.
In the Taeniaus phase, the sides of the head and the upper breast are black – paler on the throat. The rest of the under parts are barred with black and white. Intermediates occur between it and the normal phase; in other words the amount of ventral barring varies from none to a great deal. Rarely, one is almost solidly black below as well as on the back.
The eyes are grey or greyish yellow; the area around eyes, the lores, and the cere are slaty black. The bill is black; the legs yellow.
Immatures are white on the head and lower parts, some times lightly dusted with grey. The crest feathers are white at their base, then black, with a white tip. The back and wings are marbled and irregularly barred with black and white – paler on upper-wing coverts, which are white stippled with grey. The tail is marbled, grey and white, with seven or eight irregular black bars. As in the adult, the primaries are much barred.
There is a smooth transition between this plumage and the adult, making it difficult to decide whether some specimens represent variations in the adult plumage, or are not fully adult.
The most noticeable feature of the Guiana crested eagle is the projecting occipital crest on its head. Unlike the Harpy eagle, which has a bifurcated or double crest, the Guiana crested eagle has a single, undivided crest. The crest consists of feathers uniquely colored with a white base, black center, and white tip. As with other birds’ display behaviors, the crest?which can be raised and lowered?is thought to be used as a form of communication. Birds often communicate with vocal or visual displays, including colored plumage during breeding season or elaborate movement routines designed to attract potential mates. With birds such as the Guiana crested eagle, however, behavioral displays usually communicate greeting, threat, submission, or distraction. The crest’s graded or variable display (it does not have to be completely raised or lowered, but can be somewhere in between) conveys the intensity of the eagle’s impending actions. Even though the display of the occipital crest may be difficult to decipher for those studying this bird, the signals it communicates are likely to be unambiguous to others of its species.


wingspan min.: cm wingspan max.: cm
size min.: 71 cm size max.: 84 cm
incubation min.: 40 days incubation max.: 50 days
fledging min.: 85 days fledging max.: 50 days
broods: 1   eggs min.: 1  
      eggs max.: 2  

Range

Latin America : Guatemala to Northeast Argentina. Guatemala and Honduras through Central America to Colombia and S to Paraguay, extreme NE Argentina (Misiones) and S Brazil; W of Andes, ranges S only to Serrania de Baudo (WC Colombia).

Habitat

Little is known about its habits. It inhabits heavy jungle, and is said to be found exclusively in the warmest and most humid regions in almost impenetrable forest near the coast, or especially at the edges of rivers. It frequently alights on the highest dry trees of the forest.

Reproduction

Crested Eagles built nest just below the canopy in dense rainforest with lower undergrowth. The nest is built of sticks and very well taken care of. The female usually brings greenery to the nest to replace old sticks. Two eggs are laid in one brood in the middle of the rainy season. Incubation is (presumably) 40-50 days and is mostly done by the female. After hatching both parents feed the young. The young fledge after about 90 days.

Feeding habits

Like its close relative the Harpy eagle (Harpia harpyja), the Guiana crested eagle is large enough to feed on live prey such as smaller birds, opossums, and reptiles. The Harpy eagle, though, is still larger and stronger, feeding on monkeys, sloths, and other arboreal and terrestrial mammals. Eagles of this size are too large to kill prey in the air; so they surprise their prey on the ground, often decapitating their victims.

Video Crested Eagle

httpv://www.youtube.com/watch?v=f38a9G_yIFA

copyright: B. Whitney


Conservation

This species is rare throughout its vast range, and is thought to be declining moderately rapidly owing to habitat loss and hunting. For this reason it is classified as Near Threatened.
The Guiana Crested Eagle can be found in lowland tropical forest from Honduras to northern Paraguay and Argentina . Rarebird in Suriname, sometimes found in the coastal areas. Mostly in the interior, but little is known.
Crested Eagle status Near Threatened

Migration

Morphnus guianensis is sparsely distributed throughout its extensive range from Guatemala through Belize, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Venezuela, Guyana, Suriname, French Guiana, Brazil, and east Andean Ecuador, Peru, Paraguay and Bolivia to north Argentina. Presumed sedentary.

Distribution map

Crested Eagle distribution range map

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