Harpy Eagle

By Alexander Holmgren

Scientific Name: Harpia harpyja
Where in the World? Southern Central America and the northern half of South America- Mexico to Argentina
How Big?
176 to 224 cm (5 ft 9 in-7 ft 4 in) wingspan
4-4.8 kg (8.8-11 Ibs) male weight
What does it Eat?
Large tree dwelling mammals predominantly, as well as large birds, and reptiles.
How Many?
This large bird of prey is labeled as Near Threatened by the IUCN.

The harpy eagle is one of the largest eagles in the world and as such is an apex predator in its environment. Named after the mythological creature the Harpy in Greek mythology this animal is defined by its powerful claws that are stronger than those possessed by a grizzly bear, powerful wings to bear prey its own weight, and a razor sharp beak to tear flesh.

Harpy Eagle. Photo by Rhett A. Butler
Harpy eagles are related closely to both the New Guinea harpy eagle, and the crested eagle, the three species comprising the subfamily of Harpiinae, however, the harpy eagle is the only animal with the genus harpia. The bird has a jet black back with an all white belly except for a black band across the upper torso that gives way to the grey plumage of the head. Harpy eagles also possess a double crest that will flatten or rise if the eagle is alarmed or startled.

Harpy eagles are believed to mate for life and raise a new chick every two to three years. A female will lay two eggs and after fifty six days of incubation one egg will hatch while the slower chick to hatch will be completely ignored and die. After this the male will begin to feed the chick and later in the parental cycle the female will take over that duty. After roughly one month the chick will be able to stand and might even be able to stumble around the nest. At five months the chick will develop its coat of feather or fledge. This also means that the now capable of flight eaglet will leave the nest, however, it will often return in order to get a free meal from its parents. This continues from six months to a year with the parents slowly weaning the child off of this habit until it is capable of hunting for its own food. At the age of four to six, the eagle will be sexually mature and ready to produce its own children.

Harpy Eagle. Photo by Rhett A. Butler
Harpy Eagles are carnivores and are the apex predators in their environment; as such nothing is above them in their food chain. Large tree dwelling mammals make up the majority of their diet with sloths and monkeys being the largest portion of the harpy eagles diet with giant creatures such as the spider monkey being taken, killed, and brought back to the nest without so much as a break, an amazing feat of strength. They have even been known to kill larger creatures such as deer and eating them on branches closer to the ground. The most common hunting technique is called perch hunting. This entails the harpy eagle scanning for prey upon branches perches and making quick decisive swoops and killing the prey with talons. Harpy eagles usually nest in large trees at high altitudes. Large sticks are used to create a frame while soft mosses, furs, and seedpods to make it comfortable. The final result is a five foot wide and four foot thick nest that is reused for years.

While only listed as near threatened by the IUCN the harpy eagle is near extinct in its more northern territories such panama. The number one threat to the harpy eagle thus far is habitat loss. Deforestation due to agriculture, raising cattle, and logging decimates the population of harpy eagles especially due to the specific types of trees they require to build their nests and raise offspring. The harpy eagles brazen and fearless behavior also makes them a nuisance to humans since in areas where massive amounts of deforestation have occurred they can on rare occasions become predators to human livestock. This coupled with their large sizes makes them an easy target for poaching. Their slow recovery rate due to every pair of harpy eagles raising a single child also contributes to this issue.


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