Crested Eagle - Morphnus guianensis

Crested Eagle (Morphnus guianensis) eating 
snake

Family: Accipitridae
Genus: Morphnus
Species: M. guianensis

Crested Eagles are large, South and Central American raptors that live primarily in tropical and subtropical forest. They form a clade with Harpia (Harpy Eagle, Harpia harpyja) and Harpyopsis (New Guinea Harpy Eagle, Harpyopsis novaeguineae).

Physical Description:

There are dark morph and pale morph Crested Eagles. Pale morphs have a gray head, light underside, and cinnamon-rufous barring along the thighs. The wings have gray-white tips, and the primaries are barred with black and gray. The tail is black with three gray and white bars, with a light gray trailing edge. Dark morphs have black heads and a black breast, with heavier barring on the underside. In more extreme cases, dark morph Crested Eagles may be entirely black except for gray tips along the wings, gray bands on tail, and slight barring on the underside. This form was once described as the separate species taeniatus, which is why the dark morph is sometimes referred to by that name.

Both morph forms have short, rounded wings, long secondary feathers, and a long tail. Their crest comes to a single point. Eyes are gray-yellow, the beak is black, and the unfeathered legs are yellow. Adult Crested Eagles are distinguished from Harpia harpyja (Harpy Eagle) by their barred underside and lack of a black collar.

Juveniles have white heads and underside. The crest is black with a white base and tip, and the wings are barred with white and black. They reach full adult plumage after three years or so.

Their call is a sharp whistle. Listen to a Crested Eagle.

Size:

Length: 71-84 cm
Wingspan: 138-176 cm
Weight: 1.75-3.0 kg

Habitat and Distribution:

Crested Eagles live in tropical and subtropical forest, in addition to palm swamps, gallery forests, and ravines. Much of their range is in the Amazon rainforest, where there is contiguous forest. They are usually found from 0-600 meters above sea level, but have been known to live up to 1,600 m.

They live in Belize and northern Guatemala, through Honduras, Nicaragua, and Costa Rica to Panama, and then across much of Brazil, Paraguay, and northern regions of Argentina; their total range is 9,190,000 km², from 18°N to 27°S. They are not migratory birds. There are approximately 1,000-10,000 individuals.

Diet and Hunting:

Crested Eagles take medium-sized birds, mammals such as monkeys and opossums, reptiles, and frogs. They still-hunt from a perch, and may forage by flying slowly above the canopy. They hunt for guans and trumpeters under fruit trees.

Reproduction:

The breeding season is from March-April.

The nest is a large platform made out of sticks, with a shallow depression at the center, set in the fork of a tree high up in the canopy. A clutch of 1-2 eggs is laid and incubated by the female for 40-50 days, while the male brings food and fresh branches and leaves to the nest. The eggs are white to cream-colored, with light brown and gray spots. Fledging takes 103-114 days.

Conservation:

Crested Eagle numbers are declining due to shooting, competition with humans for food, and habitat loss. They are currently listed as Near Threatened by BirdLife International.

Taxonomy:

Based on molecular sequences of two mitochondrial genes and one nuclear intron, genus Morphnus was found to form a clade with genera Harpia (Harpy Eagle, Harpia harpyja) and Harpyopsis (New Guinea Harpy Eagle, Harpyopsis novaeguineae).

Other Names:

Guiana Crested Eagle, Harpyje pralesní (Czech), Guyanatopørn (Danish), Wurgarend (Dutch), Sarvikkotkas (Estonian), Pikkuharpyija (Finnish), Harpie huppée (French), Würgadler (German), Aquila crestata della Guiana (Italian), Himeougiwashi (Japanese), Brynjeørn (Norwegian), Uiraçu falso (Portuguese), Aguila Crestada, Arpía Menor (Spanish), Guianatofsörn (Swedish).

Video of a Crested Eagle:

References:

http://www.avesderapinabrasil.com/morphnus_guianensis.htm
http://avibase.bsc-eoc.org/species.jsp?avibaseid=E19434C9EE8CF258
BirdLife International (2011) Species factsheet: Morphnus guianensis. Downloaded from http://www.birdlife.org on 08/11/2011.
Global Raptor Information Network. 2011. Species account: Crested Eagle Morphnus guianensis. Downloaded from http://www.globalraptors.org on 8 Nov. 2011
BirdLife International 2008. Morphnus guianensis. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.1. www.iucnredlist.org. Downloaded on 08 November 2011.
Crested Eagle (Morphnus guianensis), Neotropical Birds Online (T. S. Schulenberg, Editor). Ithaca: Cornell Lab of Ornithology; retrieved from Neotropical Birds Online: http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=129076
http://www.planetofbirds.com/accipitriformes-accipitridae-crested-eagle-morphnus-guianensis
Ferguson-Lees, James, and Christie, David A. Raptors of the World. Houghton Mifflin Company, 2001.