Harpy Eagle

The Harpy Eagle is one of the largest and most powerful of all living eagles, a dominant apex predator of the Neotropical rainforest canopy. It ranges from southern Mexico through Central America to Brazil and northern Argentina, though it has vanished from much of its former range.

Adults have a pale gray head, a black band across the upper breast, and a striking double crest of blackish feathers that is raised into a fan-like shape when the bird is alert or alarmed. The upperparts are blackish-gray, the underparts white, and the tail is long and banded black and gray. Its most extraordinary features are its enormous yellow legs and talons, which are proportionally among the largest of any eagle, allowing it to grip and kill prey many times its own body mass.

Females are dramatically larger than males, a form of reversed sexual size dimorphism common among raptors that take large prey, and can weigh nearly twice as much as their mates.

Key field marks

• Double, pointed gray-and-black crest, raised into a fan when alarmed
• Pale gray head and neck contrasting with a black breast band
• Black upperparts and white underparts with black tail bars
• Massive yellow legs and enormous black talons
• Broad, relatively short wings and long tail suited to maneuvering through dense canopy

Similar species

The Crested Eagle (Morphnus guianensis) overlaps in range and shares a crest, but is more slender, has a single crest rather than a double one, longer proportionally, and lacks the Harpy's massive feet. No other Neotropical raptor approaches the Harpy Eagle's sheer bulk and leg thickness, making a good look at the legs and feet usually diagnostic.

Range

The Harpy Eagle occurs from southern Mexico and Central America south through the Amazon Basin to northern Argentina, though populations are now fragmented and it has been extirpated from much of Central America and parts of Brazil's Atlantic Forest.

Habitat

It depends on large, continuous tracts of lowland tropical rainforest, hunting from and nesting in emergent trees that rise above the canopy. Because each pair requires an enormous home range to find enough prey, the species is extremely sensitive to deforestation and forest fragmentation.

Migration

Harpy Eagles are non-migratory and sedentary, remaining on large permanent territories for life.

Hunting and feeding

The Harpy Eagle is a stealth ambush predator, perching quietly for long periods before flying rapid, powerful attacks through the forest canopy. Its diet consists mainly of arboreal mammals, especially sloths and monkeys, supplemented by opossums, coatis, porcupines, and occasionally large birds or reptiles.

Voice

Harpy Eagles are generally quiet away from the nest, giving high, thin, whistled calls between mates and to communicate with chicks.

Nesting and breeding

Pairs build enormous stick nests high in emergent trees such as kapok (ceiba), often reusing the same nest for years. A single egg is typically laid, and the chick remains dependent on its parents for close to two years, so successful pairs generally breed only once every two to three years.