Last updated: 5 February 2023
Eagles are among the behemoths of the avian world, ruling the skies across their territories.
There are around 60 species of eagle in the world, and they live in practically every environment ranging from the high mountains to coastlines and lowland deserts. One of the largest, most impressive, and most powerful eagles in the world is the Harpy eagle.
Here, we’re going to answer the question in detail: how big are Harpy eagles?
Harpy eagles are the third heaviest eagles in the world by body mass and the second-largest by length. With talons that measure over 4 inches, these gargantuan birds possess the largest claws of any eagle and can lift their own body weight. This enables the Harpy eagle to prey upon Spider monkeys, Howler monkeys, and sloths that weigh up to 9kg.
Harpy eagles are uncommon and are distributed through much of South America north of northern Argentina, stretching up to Mexico, but are absent from much of the west of South America.
This fierce hunter’s main prey are tree-dwelling mammals, such as monkeys and sloths, and it’s evolved superbly well to catch them.
Read on to discover exactly how long Harpy eagles are, along with plenty of other interesting facts about this colossal bird!
Harpy Eagles are colossal birds
Harpy eagles are about the third-largest eagle in the world, which makes them one of the largest birds in the world.
The female Harpy eagle is considerably larger than the male, weighing around 6 to 9kg (13 to 20lb). One exceptional female weighed 12.3kg (27lb)! The male weighs around 4.4 to 4.8kg (9.7 to 10.6lb), which makes it more than 35% smaller than the female by body mass.
In terms of length, Harpy eagles measure around 86.5 to 107 cm (2ft 10in to 3ft 6in), which makes them the second-longest eagle in the world. It’s pretty marginal, though, as the largest eagles are all similarly sized.
Harpy eagles have distinctive head crests and flat, wide faces that are somewhat humanoid from a distance. They’ve even been described as looking like a “human in a bird costume” and are potentially responsible for a number of cryptid sightings.
Harpy Eagle perched on a branch in the rainforest, Brazil
Harpy eagles have a wingspan of around 176 to 224cm (5.9 to 7.4ft). Again, females have a larger wingspan than males. Harpy eagle wingspans are shorter than the Steller’s sea eagle, Golden eagle, and White-Tailed eagle, as Harpy eagles tend to remain close to the tree canopy and don’t need to soar to the same heights as other eagles.
Harpy eagle claws are massive. The foot of a Harpy eagle female is about the same size as a human hand, and the talons measure around 3 to 5 inches (7.62 to 12.7cm). That’s about the same as a Kodiak bear!
These enormous talons excerpt around 55psi of force upon their victim - or over 50kg of crushing power. That’s easily enough to penetrate the bone and flesh of most land animals.
The large talons of a Harpy eagle
There’s no doubt that Harpy eagles are huge birds. They are larger than Golden, and Bald eagles - the largest eagle in the Americas. In addition, Harpy eagles have thick, puffy plumage and large, flat faces, which makes them appear even larger.
A large female Harpy eagle’s legs are also extremely thick - around as thick as a human wrist.
This makes them look even bigger - so big that they’re sometimes described as looking like a “human in a bird costume”!
Harpy eagle wingspans range from 176 to 224cm (5.9 to 7.4ft) - almost certainly larger than most people are tall. A flying Harpy eagle is a rare and glorious sight and is sure to shock anyone that hasn’t seen an enormous bird in the flesh.
Harpy Eagle (Harpia harpyja) in Ecuador, south America
Harpy eagles are very strong and have huge, powerful claws. Their primary prey is tree-dwelling animals, including sloths, Howler monkeys, and Spider monkeys, which weigh up to 9 to 10kg.
A large female Harpy eagle can capture, kill, and transport a large monkey weighing up to 10kg. Harpy eagles have the highest weight carrying capacity alongside the Philippine eagle, Golden eagle, and Crowned eagle. The Harpy eagle holds the Guinness World Record for the strongest bird of prey.
Few birds hunt prey this large, though other eagles have been observed tackling deer. Even so, the fact that the Harpy eagle can reliably target monkeys shows how formidable this bird is, as monkeys aren’t exactly easy prey either!
Harpy Eagle bathing in Brazil
Harpy eagles live across the lowland rainforests of Central and South America - a region where there are many medium-to-large land mammals such as monkeys and slots.
These are the ideal prey for a sizable tree-dwelling eagle, and Harpy eagles have evolved to take advantage.
All eagles are large, as they’re apex predators - carnivores that sit towards the top of the food chain. Harpy eagles have no predators in the wild and have evolved to become swift and strong in order to catch their favored meaty prey.
While all eagles are carnivores and hunt primarily for meat, Harpy eagles prey on particularly large prey in the form of monkeys. Monkeys are intelligent, fast, and strong - they’re no easy catch. This is also why the Harpy eagle evolved some of the largest talons of any land animal - their claws are almost as large as a grizzly bears.
Harpy Eagle perched on a branch
Harpy eagles are some of the largest eagles. In fact, by some measures, female Harpy eagles are probably the biggest eagles of all, though they’re very closely matched with the Steller’s sea eagle and Philippine eagle.
Amongst birds of prey, all eagles take the second spot to condors, which are significantly larger in all respects. An Andean condor's wingspan is nearly 1m more than a Harpy eagle's!
There is no doubt that the Harpy eagle is a colossal bird, however, standing at least as tall as a small child.
Their claws are as big as a human hand, and their talons are as long as a Grizzly bear’s. Harpy eagles are covered in a dense down with distinctive head crests and wide, flat heads, making them appear very large.
Harpy eagles are often dubbed the most powerful; bird of prey for their ability to hunt and kill monkeys. Conversely, despite its massive size, an Andean condor feeds largely on carrion. Few birds can kill such large prey as the Harpy eagle.
Harpy Eagle walking along the ground
It’s difficult to truly specify the largest eagle in the world. The heaviest Harpy eagle recorded weighed 12.3kg (27lb), whereas the largest Steller’s sea eagle weighed 12.7kg (28lb). Harpy eagles appear very large due to their thick plumage, massive claws, and distinctive head crests. They’re definitely up there with the most giant eagles in the world!
Harpy eagles can’t pick up humans, but they could pick up a baby. The average 1-year-old weighs around 9 to 10kg, which is about the maximum a Harpy eagle can carry.
This is about the same weight as a sloth or Spider monkey. However, a Harpy eagle could probably kill an adult human if it were to target the cranium accurately - their claws pack enough crushing power to crunch through a human skull.