Eagles are magnificent birds of prey usually thought to symbolize strength and power, like in the case of the United States’ national bird, the Bald Eagle. With much variation, ranging from the powerful South American predator, the Harpy Eagle, to the bright-faced Bateleur Eagle, eagles are a fascinatin type of bird.
However, there’s actually no defining group of ‘eagles’ – eagle is simply a term typically used to classify larger birds of prey capable of carrying off large kills. With that being said, some eagles are surprisingly small! Here, we’ve compiled a list of the world’s smallest eagles – while they’re small, they’re still mighty.
1. Pygmy Eagle
The pygmy eagle (Hieraaetus weiskei), also known as the New Guinea hawk-eagle, is a small eagle species endemic to New Guinea. They dwell in subtropical & tropical forest habitats, and are brown and white in coloration. The pygmy eagle is known to be one of the smallest eagle species; they are only 38 to 48 cm (15 to 19 in) in length, and females (the larger of the sexes) weigh on average only 555 g (1.224 lb).
In comparison, the bald eagle has an average length of 70–102 cm (28–40 in), and an average weight of 5.6 kg (12 lb) for females and 4.1 kg (9.0 lb) for males! They are swift in flight, and primarily dive to obtain their prey, which largely consists of other birds such as the brown cuckoo-dove.
2. Great Nicobar Serpent Eagle
The Great Nicobar serpent eagle (Spilornis klossi) is believed to be the smallest recorded species of eagle; they have a weight of only 450 g (0.99 lb), and an average length of 38 to 42 cm (15 to 17 in). That’s not very large at all for a bird of prey – for reference, the common raven weighs 1.47 kilograms (3.2 pounds) on average – over three times as much as this small eagle!
They are brown overall with a barred tail and black cap, along with bright yellow feet & facial skin. These birds are only found on the Nicobar islands, and are listed as Endangered; it’s believed they have a very small population size of around 250 mature birds.
3. Little Eagle
The little eagle (Hieraaetus morphnoides)is a small eagle species found in Australia; weighing 815 g (1.8 lb), they are comparable in size to the peregrine falcon. Although the little eagle inhabits most of Australia, they prefer open woodland, grassland and arid regions, and will avoid dense forest habitats. Sadly, the little eagle is struggling to keep up in today’s Australia; after invasive rabbits began to decline, the eagle had less available food, as many native animals of comparable size are extinct or endangered.
They are agile, fast-paced hunters like many other eagle species, but they will also feed on carrion when it’s a wiser choice than expending energy looking for prey. Males have longer wings in proportion to their body, but are also only half the size of the females; females can also be distinguished by being darker overall in color.
4. Rufous-Bellied Eagle
The rufous-bellied eagle (Lophotriorchis kienerii)is a small eagle found in forested regions of tropical Asia. Adults have unmistakable patterns; they have a black hood and a small crest, with chestnut-colored underparts and wing coverts accented by their white throat and chest. They perch almost stiffly, keeping their bodies in a sharp upright stance.
They are mainly found in hilly forest habitat, where they predate on birds and mammals. During the breeding season, both parents collaborate to build a large platform nest of sticks and branches in a tree; only a single egg is laid per clutch, and parents take turns defending the nest, incubating the egg and feeding the chick.
5. Cassin’s Eagle
Cassin’s eagle, also known as Cassin’s hawk-eagle (Aquila africana), is a small eagle species found in rainforests across western, central and eastern Africa. They primarily prey on smaller birds and tree squirrels, although it is believed other mammals of comparable size may be preyed upon. They are annual breeders, laying only 1-2 eggs per clutch. The dense forests these species inhabit has made surveys and studies in the wild difficult, so there’s still research lacking on what the lives of these eagles look like.
6. Philippine Serpent Eagle
The Philippine serpent eagle (Spilornis holospilus)is a small to medium sized eagle found across the Philippine archipelago. As in many birds of prey, females are significantly larger than male counterparts; females weigh 1.6 kilograms (3.5 pounds), while males weigh 603-672 grams (1.3–1.5 pounds). They give a loud, rising whistle during flight, which means you’re more likely to hear them before you lay eyes on them!
While the species is not currently deemed to be at risk of extinction, their population has declined in recent years due to deforestation in the Philippines. Like their name suggests, they feed on reptiles, including snakes; they also feed on amphibians and may take other live prey such as mammals and birds.
Conclusion
Just because a bird is small doesn’t mean it’s not powerful, and eagles are no exception. These smaller-sized eagles are still adept hunters with interesting lives. While many of these eagles may be difficult to spot in the wild, given that some of them live in remote areas or are secretive, you may be able to visit a zoo or aviary hosting some of these fascinating birds. Interested in learning more, or helping these birds live better lives?
Consider supporting an organization that participates in conservation efforts for one or more of these species. Many birds of prey around the world have declining populations due to less available prey, habitat destruction, and global warming – make a difference by doing what you can to support them.
