Tasmanian wedge-tailed eagle facts for kids
Quick facts for kids Aquila audax fleayi |
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| Conservation status | |
Scientific classification  |
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| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Accipitriformes |
| Family: | Accipitridae |
| Genus: | Aquila |
| Species: | |
| Subspecies: |
A. a. fleayi
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| Trinomial name | |
| Aquila audax fleayi Condon & Amadon, 1954
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The Tasmanian wedge-tailed eagle (Aquila audax fleayi) is a large bird found only in Tasmania. It is a special kind of subspecies of the more common wedge-tailed eagle. Sadly, this amazing bird is currently endangered, which means there are not many left.
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About the Tasmanian Wedge-tailed Eagle
These eagles belong to a group of large eagles called Aquila. They have long, rounded wings that look like they have deep cuts at the tips. They also have very strong legs and sharp claws. Their nostrils are shaped like ears! The Tasmanian wedge-tailed eagle is the biggest of all the wedge-tailed eagles.
An adult Tasmanian wedge-tailed eagle can be between 100 and 110 cm long. Their wings can stretch out to be 1.9 to 2.3 meters wide. They usually weigh between 3.5 and 5.5 kg. Female eagles are bigger and heavier than males. They are ready to have their own chicks when they are about 4 to 6 years old.
The largest wingspan ever recorded for an eagle was from a Tasmanian wedge-tailed eagle. A female eagle in 1931 had wings that stretched 284 cm wide! Another female was almost as big, with a wingspan of 279 cm.
Young eagles are light brown with a dark blond neck. Their tail and flight feathers are dark. As they get older, their feathers become almost black. Adult eagles have pale silver at the base of their main wing feathers. This makes a "window" shape when you see them flying from below. Male eagles are dark brown with a reddish-golden neck.
When it's not breeding season, these eagles are usually quiet. They often stay in pairs or as a family. During the breeding season, you might see them doing amazing aerial displays in the sky.
Eagle Life and Habits
Wedge-tailed eagles are powerful hunters at the top of the food chain. They protect large areas of land as their home.
Reproduction and Family Life
Wedge-tailed eagles usually stay with the same partner for their whole lives. They stay together all year round. When they are looking for a mate or strengthening their bond, they perform amazing flying shows. This special time usually starts in late June. They begin to fly more and fix up their nests. This activity is busiest in late August. In August, just before they lay eggs, they decorate their nest with fresh green leaves. They keep doing this throughout the breeding season.
They usually lay one or two eggs, but most often just one. This happens in late August or early September. The eggs are whitish-grey with a few brown spots. They are about 73 by 58 mm in size. The female eagle sits on the eggs for 43 to 45 days to keep them warm. During this time, the male eagle brings her food.
After the chick hatches, the female feeds it for the first few weeks. When the chick is about six to eight weeks old, it can start feeding itself. Then, both parents bring food directly to the nest. Chicks stay in the nest for up to 90 days before they are ready to fly. After they fly, they stay near the nest for several more weeks. Young eagles rely on their parents for food for at least three months. They might even stay with their parents until the next breeding season. Once they leave their parents, young birds fly to many different places.
What Eagles Eat
Wedge-tailed eagles are meat-eating birds that hunt over many different areas. These include open fields, grasslands, and pastures. They also eat dead animals if they find them. They mostly eat rabbits, hares, birds like the Tasmanian nativehen, wallabies, and possums. Young eagles are not as good at hunting yet, so they often eat more dead animals. Adult eagles also eat a lot of dead animals in winter.
In the countryside of Tasmania, these eagles eat:
- Rabbits, hares, and cats (about 45% of their diet)
- Wallabies, possums, echidnas, and wombats (about 30%)
- Birds (about 10%)
- Sheep and goats (about 7.5%)
- Reptiles (about 5%)
The rest of their diet is made up of other things.
How They Hunt
The wedge-tailed eagle usually catches its prey by swooping down from a high spot. They launch themselves from a perch and attack animals on the ground. Sometimes, but less often, they catch prey in the air. They usually hunt during the day. They eat their prey where they catch it. But during breeding season, they take a lot of food back to the nest for their young. Eagles usually do not bring dead animals back to the nest for their chicks.
Even though they can kill animals much bigger than themselves, most of the animals they catch are smaller. They usually catch prey that is about half their own weight or less. Wedge-tailed eagles cannot carry more than about one-third of their own body weight.
Where Eagles Live
Distribution in Tasmania
The Tasmanian wedge-tailed eagle lives all over Tasmania. There have been only a few sightings on King Island and the smaller islands in Bass Strait. These eagles can hunt in all kinds of places, from coastal sand dunes to mountain tops. We don't know of any eagles moving between Tasmania and mainland Australia. However, one bird was seen over Curtis Island around 1985.
Even though they can hunt in forests, how thick the trees and plants are affects how much food they can find. So, there are fewer eagles in the western and southwestern parts of Tasmania. The forests there are often shorter and scrubbier. There are more eagles in areas that have a mix of forests, farms, grasslands, wetlands, and rivers. In eastern and northern Tasmania, you might find one pair of eagles in an area of 20–30 km². In western and southwestern Tasmania, it's more like one pair per 1200 km².
Nesting Places
Wedge-tailed eagles usually build their nests in very old, tall native forests. These forests are mostly made up of large eucalypt trees and are bigger than 10 ha. However, they can also nest in rainforests or even in single eucalypt trees within Acacia forests. The trees they choose for nesting are usually among the tallest in the area, often taller than 27 m. They usually pick trees on slopes that are protected from strong winds. The top of the nest tree is often lower than the top of the nearby ridge.
An eagle pair might have up to three or five nests in their territory. They will choose one nest to use each year. Eagles often return to the same nesting spots. Some nests have been used for at least 50 years! Nests are usually about 200 m apart. But they can be more than 1 km apart in places where good nesting habitat is hard to find.
Protecting the Eagles
The number of Tasmanian wedge-tailed eagles has gone down for several reasons. These include:
- Less success in raising chicks because their nests are disturbed.
- Loss of their natural homes.
- A small number of breeding eagles.
- Fewer adult eagles.
- Too many eagles dying because of human actions and other reasons.
The wedge-tailed eagle is a fully protected bird. It is against the law to kill one. About 20% of these eagles live in special protected areas. Efforts have been made to help eagles have more chicks on private land. This is done through special agreements and plans with landowners. In Tasmania, 60 landowners have made contracts, and 20 have made agreements to help protect the eagles.
Most of the known eagle nests (over 80%) are on State Forest land and private property. This is partly because most of the good eagle habitat is on these lands. It's also because many nest searches happen when forestry activities are planned.
A. a. fleayi will not nest in areas where there are many people. These eagles are very shy when they are breeding. They are likely to leave their nest if they are disturbed.
Population Changes
Tasmania's wedge-tailed eagles have less variety in their genes than eagles on the mainland. They have been separated from mainland Australia for 8,000 to 10,000 years. This happened after the land bridge across Bass Strait disappeared. We don't know exactly how many eagles there were in Tasmania in the past. But old records suggest they were spread out but not common. They might have benefited from rabbit plagues, which gave them more food. However, poisoning has killed many eagles, along with other harmful actions.
The number of successful breeding pairs has gone down. On average, only 95 pairs successfully raise chicks each year. About 69% of eagle territories had active nests, or nests that were known to have at least one egg. About 53% of these were successful in raising a chick that could fly. Each year, about 50% of young eagles die. About 30% of other young eagles die, and 5% of adult eagles die. Tasmania only has 220 nesting territories. However, not all territories have two adult eagles. It seems to take a long time for new adults to replace those that are lost. This suggests there aren't many extra eagles without territories. It also means the adult population is likely less than 440 birds.
Images for kids
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Silhouette of a wedge-tailed eagle and a forest raven (crow).
