English            -               Harpy Eagle

Portuguese     -               Gavião-real

Latin                -                Harpia harpyja          

The Harpy Eagle is the largest, most powerful raptor in the Americas, even larger than the Golden Eagle. Its name refers to the harpies of Greek mythology, monsters in the form of a bird with a human face. The species inspired the design of Fawkes the Phoenix in the Harry Potter series and the Harpy Eagle is the national bird of Panama.                                           

The Harpy Eagle has dark grey feathers with a white under side. A black band of plumage spans its neck and a fan of grey feathers crowns its head. Male and female plumage are identical. The only real difference between the sexes, as is often the case with most birds of prey, the females are larger than males. The Harpy Eagle can grow to 100 cm in length. Females can weigh up 9 kg. Males can weigh up to 5 kg. They can have a wingspan of up to 7 feet across. Its wings are relatively short for its size, enabling the bird to manoeuvre through its thick-forested surroundings to capture prey. Their yellow feet and legs make way for very big black talons that are around 12 cm in length. The Harpy Eagle’s call is a plaintive, penetrating scream, described as ‘wheeeeeeee’ or ‘wheeeeoooooo’, which is repeated several times

The Harpy Eagle has an extensive distribution across Central and South America, from southern Mexico southwards to Paraguay, southern Brazil and north-eastern Argentina. However, it is quite sparsely distributed across its range and is thought to be locally extinct in some areas, particularly in parts of Central America. The Harpy Eagle primarily is a lowland species, it typically inhabits tropical and subtropical evergreen forests below elevations of about 900 metres, although it may occasionally be found up to 2,000 metres. They are able to adapt to a degree of habitat disturbance, as long as sufficient forest patches remain. The Harpy Eagle usually moves about within the forest canopy and rarely soars above it. 

A hunting carnivore and an apex predator, the Harpy Eagle preys primarily on tree-dwelling mammals like sloths, monkeys and opossums. They will also prey on other arboreal animals like birds and large lizards  and they will even prey on land mammals given the opportunity, including porcupines, squirrels, opossum, anteaters and armadillos. So not to compete with each other for food, the females generally target larger prey because of their size, leaving smaller prey for the males.

Harpy Eagles reach adulthood when they are about 5 years old. After a suitable partner is found, it is time to look for a nesting site. Harpy Eagles nest in some of the tallest trees in the forest. They pick the highest point on the trunks of trees, just where the branches begin to spread out, at around 40 meters of the ground. Nests are composed of large sticks and branches gathered from nearby trees. In all, the pair will lay down more than 300 branches! The result is a nest that can be 6 feet in diameter and more than 1 foot deep. Some Harpy Eagle pairs reuse the same nest over and over, while others might have several nests they use off and on over the years. When the nest is completed, the female will lay one or two large white eggs. Though the male may assist in incubation, the female does the most sitting on the eggs to keep the chicks developing inside warm and safe. She needs to incubate her eggs for approximately 55 days. If 2 eggs are laid, in most case only one chick will survive. Though scientists don’t fully understand why, some believe that Harpy Eagles lay the second egg as a “backup” in case something happens to the first and since raising one Harpy Eagle chick takes so much time and energy, it would be too difficult to try to raise two chicks. Harpy Eagles are wonderful parents that work hard to protect their chicks. From the time the female first lays her eggs until the nestling is about 4 months old, she will spend almost all her time at the nest. Meanwhile, the male spends his time and energy looking for food for himself, the female, and his young. A newly hatched Harpy Eagle chick is so small that it fits perfectly into the palm of a person’s hand. In only 5-6 months though, it will reach adult size. Because the chick grows so quickly, it needs to eat a lot and it needs to eat often. When the chick is very young, the mother will tear off small pieces of meat for the chick and delicately feed it with her bill. As the chick grows, it will be able to tear off and eat the meat on its own. At around 5-6 months of age, the young eagle will fledge, or fly for the first time. Its first few flights might be shaky and awkward, but after only a few days, it will be flying almost as well as its parents. The young bird will remain dependent on the adults for the first one to two years of life. When it is hunting well enough on its own, the juvenile will disperse, or leave its parents’ territory and look for a home of its own. When a young bird turns 4 or 5 years old, it will begin looking for a partner and the cycle of reproduction will begin all over again. A pair of Harpy Eagles generally raises young every two years. They normally won’t lay more eggs while they are still caring for a young bird in their territory.

The Harpy Eagle is classified as a species “Near Threatened” on the IUCN Red List and is listed on Appendix I of CITES. Although the Harpy Eagle still occurs over a considerable range, its distribution and populations have dwindled considerably. It is threatened primarily by habitat loss due to the expansion of logging, cattle ranching, agriculture, and prospecting. Secondarily, it is threatened by hunting, for being a threat to livestock and/or a threat to human life, due to its great size. Although not actually known to prey on humans and only rarely on domestic stock, the species’ large size and nearly fearless behaviour around humans reportedly make it an “irresistible target” for hunters.

Photos of the Harpy eagle were taken at Parque das Aves - Foz do Iguacu - Parana