What is a Wedge-Tailed Eagle?

The wedge-tailed eagle is bird of prey — Australia's largest — and among the biggest of the world's raptors. In addition to Australia, this eagle is found in southern New Guinea and in Tasmania. The scientific name for the wedge-tailed eagle is Aquila audax.

As their name suggests, wedge-tailed eagles have a wedge-shaped tail. Adults are dark brown or black with feathered legs down to the toes. On average, they are 38 inches long (96 cm), weighing roughly 9 pounds (4 kg). With a wingspan of 8 feet (2.5 m), these eagles can soar on thermals for up to 90 minutes and at heights up to 6,562 feet (2,000 m).

Wedge-tails eat primarily rabbits, but are capable of taking down a lamb, or when hunting in groups, a kangaroo. They will also eat lizards, large birds, and other small animals. Additionally, they are frequent carrion feeders, sometimes feeding on large carrion in groups of 20 or 30. With incredibly keen vision, this eagle hunts by soaring through the air at high altitudes and plunging down on its prey to kill. It will then eat its meal where it lays.

Found mostly in forests and open country, the wedge-tailed eagle tends to avoid rainforests and coastal areas. Mating for life, a pair will be territorial around its nesting site, but share hunting grounds with other wedge-tails. The area of the nesting territory varies with availably of food sources. Nests are sometimes placed as close together as 0.6 miles (1 km) or as far apart as 2.5 miles (4 km).

Wedge-tailed eagles usually build nests in the tallest tree available in their territories. If the area has no trees, they may build nests on cliff faces or in shrubs. The nests, maintained over years, can be as large as 6.5 feet (2 m) wide and 10 feet (3 m) deep. Breeding occurs in April through September.

Over a few days, females lay two to four eggs. Both parents will incubate the eggs during a 45 day period, and once hatched, both parents share in the responsibility of feeding the young. The male will hunt for the food, and the female will tear the caught prey into manageable bits to feed to the hatchlings.

Usually only one hatchling will survive to fledge. Hatchlings compete for food and the largest may kill its smaller competitors. For five weeks the fledging is nest-bound, and once fledged stays with the parents approximately three months. Juvenile eagles are medium brown and darken through their first decade of life.

The wedge-tailed eagle is endangered and protected by Australia's National Parks and Wildlife Act. In the 1920s-60s, these birds were hunted and killed in huge numbers because they were thought to attack farmer's sheep. Sometimes as many as 30,000 birds would be killed in a single year.