Species Fact Profile: Harpy Eagle (Harpia harpyja)

                                                                        Harpy Eagle

Harpia harpyja (Linnaeus, 1758)

Range: Central and South America, from southern Mexico southwards to eastern Bolivia, southern Brazil, and northern Argentina.  Almost extinct throughout much of Central America, except for Panama

Habitat: Tropical Lowland Rainforest.  Prefer undisturbed forest, but sometimes found in open patches.  Generally found in the canopy

Diet: Monkeys and sloths, but will also eat large birds (such as macaws), lizards, rodents, other small mammals (opossums, porcupines, coati) and sometimes small deer

Social Grouping: Very territorial, will drive out intruders.  Active nests are usually 3-5 kilometers away from one another

Reproduction:  Monogamous, often for life.  Breeding season coincides with the start of the rains, usually April or May.  Nest is built in the upper branches of a tall tree, usually 27-43 meters above the ground and consisting of a woven stick platform lined with plants and fur.  They are quite large (1.2 meters thick, 1.5 meters across) and may be reused year after year.  2 eggs are laid, but only 1 chick raised.   Eggs incubated for 56 days and cared for by both parents.  Female does most of the incubation while the male hunts.   Chick reaches adult size at 5 months, fledges at 6-7 months, but stays with parents for an additional few months, begging for food, remain in parents’ territory for a year.  Reach maturity at 5-6 years old.  Pairs breed every 2-3 years

Lifespan: 25-35 Years

Conservation Status: IUCN  Near Threatened.  CITES Appendix I.  USFWS Endangered

• Largest species of eagle (rivaled by Steller’s sea eagle and the Philippine eagle), largest bird in Central America.  Body length 89-102 centimeters with a wingspan of up to 2 meters.  Females weigh 7-9 kilograms (one exceptionally large female weighed 12.3 kilograms), larger than males at 5-8 kilograms
• Sexes alike.  Dorsal plumage feathers typically black or dark gray, with the breast, belly, and flanks flight grey with horizontal black stripes.  The head, thighs, and vent are a lighter gray color, with a dark band across the nape of the neck.  The tail is gray with horizontal black bars.  The beak is black; the feet are yellow with black talons measuring up to 12.5 centimeters long. 
• The head is crowned with long, black feathers which stand erect when the bird is threatened or excited, possibly channeling sound to the ears.  One of the few diurnal raptors with a facial disk
• Relatively short wings and long tails, which act as a rudder.  Not built for soaring, but made for agile, maneuverable flight among the branches, traveling relatively slowly from tree to tree.  Can fly straight up, able to ambush prey from below as well as from above.  Can reach speeds of up to 80 kilometers per hour
• Their predation of capuchins and other monkeys is thought to benefit many birds, who would otherwise lose their eggs and chicks to monkey predation
• Predominately hunt from a perch, may wait for a day for prey to appear.  Prey is snatched from the canopy or (less frequently) off the forest floor and carried away to a perch to feed.   If the prey is too large, the bird will eat as much as possible so that it will be light enough to carry away.  Size difference of male and female allows them to specialize in prey of different sizes.
• Primary cause of decline is habitat loss, require undisturbed habitat, tall trees for nesting.  Also threatened by shooting.  The birds are sometimes accused of stealing small livestock (lambs, piglets), which probably does not occur often due to their intolerance for disturbed habitats where people and domestic animals are likely to be found.
• National bird of Panama, depicted on the Panamanian coat of arms; state bird of Parana, Brazil.  A harpy released in Belize in 2009 was dubbed “Hope,” a UN Ambassador for Climate Change.  Appears on the Venezuelan 2000 bolivares Fuertes bill.
• Captive breeding efforts were initiated at the Peregrine Fund’s headquarters in Boise, Idaho.  Chicks are born, but at a slow rate – 10 surviving chicks in 7 years.  The decision was made to construct a new Neotropical Raptor Center outside of Panama City.  The more suitable climate resulted in 17 hatchling eagles in the first year.  Between 1998 and 2008, when the program ended, almost fifty eagles were released into Panama and Belize.