Aquila audax | Wedge-tailed Eagle

The Wedge-tailed Eagle

The eagle that rides the inland thermals

A huge dark eagle rides the thermals over inland Australia. Its tail ends in a long wedge, of course. No other raptor there looks the same. Wingspan runs well past 2 m.

Some birds reach 2.84 m across. Females outweigh males by a wide margin. The bird spends hours aloft each day. It scans open ground for movement.

Rabbits make up much of the diet. Because the eagle can soar for hours at almost no cost, it covers more ground in a day than any ground hunter could.

Family tree

Accipitridae, the hawks and eagles

The species sits in the family Accipitridae. John Latham named it in 1801. About 11 species now sit in the genus Aquila. All are large, dark, booted eagles.

The osprey belongs to its own family, Pandionidae. That bird hunts fish and nothing else. Both are big raptors with hooked beaks, yet the two families parted long ago and never shared a diet.

Dark, huge and wedge-tailed

How to tell one

Body length runs 81 to 106 cm. Wingspan reaches 2.84 m at most. Weight falls between 2 and 5.3 kg.

Females are the larger sex. Plumage is dark brown to nearly black. A tawny patch covers the nape.

Feathers reach down to the toes, in fact. That tail is long and wedged, not square, while the wings are long and fingered. Nothing about the shape is built for speed, and the whole bird is made for slow, high, endless soaring over open country.

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Open country and arid scrub

Where it lives

Open country suits this eagle best. Arid scrub and plains are prime ground. Woodland edges are used for nesting, in turn.

Truly dense forest is avoided. Its range covers all of mainland Australia. Tasmania and southern New Guinea are included.

Tall trees near open hunting ground matter most. Sheep stations suit it well, since rabbits, lambs and winter carrion are all easy to find in one place.

Rabbits and carrion

What it eats

Rabbits are the staple across much of the range. Young kangaroos and wallabies are taken. Lambs are killed at times, though rarely.

Reptiles, birds and insects fill gaps as well. Carrion is eaten all year round. Roadkill draws birds in numbers.

Pairs sometimes hunt together. One bird flushes prey, the other strikes. Because rabbits were released across the continent long ago, this eagle now thrives on a prey animal that is not native to Australia at all.

One huge stick nest for life

The breeding cycle

Pairs mate for life. A territory is held all year. Nests are huge piles of sticks. They usually pick the tallest tree.

In addition, both birds add material each season. One to 4 eggs are laid, usually 2. Incubation lasts 42 to 48 days. She does most of it.

Chicks fledge at about 70 to 90 days. After fledging the young stay with the parents for months, since hunting on open ground takes far longer to learn than the adults make it look.

Least Concern

Conservation

The IUCN rates the species as Least Concern. Numbers rose after rabbits spread. The bird is common over most of its range.

Poisoning remains the main threat, however. Even so, shooting kills birds near sheep runs. Wind farms and power lines take others.

In addition, nest trees are lost to clearing. Unlike the barn owl, which nests in almost any hollow or shed, this eagle needs one tall tree that has stood for decades. That slow need means a lost nest site cannot be replaced quickly, even where food stays plentiful all year long.

Side by side

How It Compares

Common misreadings

What People Get Wrong

• The eagle kills many lambs. Lamb losses are rare and rabbits dominate.
• The wedged tail marks the male only. Both sexes carry it.
• Big raptors are scarce in Australia. This eagle is common across the continent.

Going further

Sources and Further Reading

• Wikipedia, Wedge-tailed eagle
• IUCN Red List, Aquila audax. The IUCN Red List of Threatened Species.
• Animal Diversity Web, University of Michigan. Aquila audax.
• Debus, S. 2017. Australasian Eagles and Eagle-like Birds. CSIRO Publishing.

Quick hits

Five things to remember

• Wingspan can reach 2.84 m in big females.
• The wedged tail gives the bird its name.
• Pairs hunt together and share the kill.
• Rabbits, a non-native prey, now feed most of the population.
• One nest reused for years can weigh as much as a small car.