Common Kestrel vs Harpy Eagle
Falco tinnunculus compared with Harpia harpyja
Side-by-Side Comparison
| Attribute | Common Kestrel | Harpy Eagle |
|---|---|---|
| Scientific Name | Falco tinnunculus | Harpia harpyja |
| Order | Falconiformes | Accipitriformes |
| Family | Falconidae | Accipitridae |
| Conservation Status | Least Concern | Vulnerable |
| Length | 34.0 cm (13.4 in) | 100.0 cm (39.4 in) |
| Wingspan | 74.0 cm (29.1 in) | 200.0 cm (78.7 in) |
| Weight | 190.0 g (6.70 oz) | 7500.0 g (264.55 oz) |
| Diet | Primarily voles and mice, also lizards, large insects, and small birds. Hunts by hovering at … | Arboreal mammals including sloths, monkeys, and opossums, which make up over 70% of the diet. … |
| Clutch Size | 1-7 | 2-3 |
| Population Trend | — | — |
Size Comparison
Habitat Comparison
Common Kestrel
Open country including farmland, grasslands, moorland, and urban areas. Common along motorways and in cities across Europe.
Harpy Eagle
Tropical lowland rainforests, requiring large tracts of continuous forest with tall emergent trees for nesting.
Song & Call Comparison
Common Kestrel
A shrill, repeated 'kee-kee-kee-kee' or 'kik-ik-ik', especially near nest. Alarm call is a nasal chattering. Generally less vocal than larger falcons. Calls ring clearly in open country.
Harpy Eagle
Rarely heard; emits mournful whistled screams 'wheee-oo' and low croaking grunts near the nest. Vocalizations poorly documented given its remote Amazonian habitat.
Geographic Range & Migration
Common Kestrel
Europe, Asia, and Africa. One of the most common and widespread raptors in the Old World.
Harpy Eagle
Central and South America from southern Mexico through Brazil and northern Argentina. Range is shrinking due to deforestation.
Conservation Status
Common Kestrel
Harpy Eagle
How to Tell Them Apart
Common Kestrel
Males have a blue-grey head and tail with a rufous back spotted with black. Females are rufous-brown with heavy barring. Both have a dark moustachial stripe.
Short, hooked grey bill with a yellow cere
Harpy Eagle
Slate-black upperparts and head with a pale grey breast and white underparts with black barring. A distinctive split grey crest rises when the bird is alarmed.
Massive dark hooked bill, one of the largest of any eagle
About These Birds
Common Kestrel
The common kestrel is Europe's most abundant falcon, famous for its ability to hover motionless in the wind while scanning for prey. Research has shown kestrels can see ultraviolet light, allowing them to detect vole urine trails that reflect UV. The species has adapted remarkably well to urban environments.
Harpy Eagle
The harpy eagle is among the most powerful raptors in the world, with talons as large as a grizzly bear's claws. It is the national bird of Panama. Deforestation poses the greatest threat to this species, as each breeding pair requires a vast territory of undisturbed forest.