How Much Weight Can an Eagle Carry? Lift Limits and Myths

Why eagles cannot lift their own weight

To carry prey, an eagle must create enough lift to support both its own body and the extra load. Its wings are already working hard to hold up a body of 3–9 kg (7–20 lb), depending on the species. Adding a load that is as heavy as the eagle itself would roughly double the lift needed, which is beyond what wing muscles can produce for more than a moment.

Taking off is the hardest part. From the ground, without speed or wind, an eagle can lift much less than it can carry once airborne. That is why eagles prefer to grab prey while already moving, use a downhill takeoff, or take off into the wind. With a strong wind or a slope to launch from, an eagle can manage noticeably more.

How much can different eagles carry?

These are typical ranges from studies of prey remains and field observations, not strict limits. A strong female, a good wind or a downhill glide can allow more, and very heavy prey may be cut up and carried in pieces.

Bald eagles and heavy fish

The bald eagle catches most fish of about 20–75 cm (8–30 in) in length, with a preference for fish around 36 cm (14 in). Occasionally it seizes something too heavy to lift. Rather than let go, an eagle may be dragged down onto the water and then “row” itself to shore, using its wings like oars while still gripping the fish. This behavior has been filmed many times in North America.

When carrying a fish, a bald eagle slows to about 48 km/h (30 mph), compared with 56–70 km/h (35–43 mph) in normal flight, a clear sign of how hard the extra weight is to carry.

Golden eagles and large prey

The golden eagle regularly carries hares and marmots of a few kilograms to its nest, sometimes in parts. Yet it is also able to kill animals far heavier than itself, such as deer fawns, chamois kids, young pronghorn and foxes. Those are not carried away. The eagle eats on the spot, returning to the carcass for days if it is not disturbed.

Golden eagles have also been seen knocking young goats and sheep off cliff ledges, so the fall does the work. This is rare and is not a common way of hunting. Their usual prey is described in What do golden eagles eat?.

The harpy eagle: the strongest eagle?

The harpy eagle of the Central and South American rainforest has the largest talons of any living eagle. Females, which weigh 6–9 kg (13–20 lb), are much larger than males and take bigger prey.

Studies of harpy nests show that prey brought home usually weighs 1–4 kg (2–9 lb), mainly sloths and monkeys plucked from branches. Harpies have been recorded carrying prey up to roughly half their own body weight. Reports of females flying off with much heavier animals exist, but they are hard to verify, and it is likely that such prey is not carried far.

Can eagles carry off children or pets?

Folklore in many cultures tells of eagles snatching babies, but there is no well-documented modern case of a wild eagle flying off with a child. Even a newborn baby weighs about 3–4 kg (7–9 lb), already at or beyond what a large eagle can lift from the ground, and toddlers weigh several times more.

The most famous “evidence” is a video that went viral in December 2012, showing a golden eagle swooping on a toddler in a Montreal park. It was quickly revealed as a hoax, created with computer animation by students at a Montreal animation school.

In prehistory, the story may have been different. Scientists studying the Taung Child, a fossil skull of an early human relative from South Africa, about 2.8 million years old, have argued that damage to it matches marks left by a large eagle similar to the crowned eagle. The idea is still debated, but if it is right, large eagles sometimes preyed on very small early human relatives.

Eagles do occasionally take small animals such as cats, small dogs and chickens, especially where natural prey is scarce. Such cases are rare, and like other prey, the animal would need to be light enough to lift.