The Australian bird that is known for mimicking the sound of a chainsaw is the wedge-tailed eagle. This large bird of prey is found throughout much of Australia and is the country’s largest bird of prey. When defending their nests or young, wedge-tailed eagles produce a startlingly accurate rendition of a chainsaw motor starting up and revving. It is an unusual and rather creepy vocalization that has earned the wedge-tailed eagle the nickname “the chainsaw bird”.
Physical Description
The wedge-tailed eagle is a large raptor with long, broad wings and a short, wedge-shaped tail. Adults have mostly dark brown plumage with reddish-brown wings and thighs. The tail is pale with a broad black terminal band. Adults have pale legs that contrast sharply with their dark plumage. The wedge-tailed eagle has a wingspan of over 2 meters, making it one of the largest eagles in the world. Males and females look similar, but females are around 25% larger than males. A female wedge-tailed eagle can weigh over 5 kilograms, while the smaller males weigh around 3 kilograms.
Range and Habitat
The wedge-tailed eagle is found across much of mainland Australia including Tasmania. It occupies a wide range of habitats from rainforests to arid shrublands. However, it has a preference for open habitats such as woodlands, shrublands, grasslands and agricultural areas. The wedge-tailed eagle builds a large stick nest high up in a tree and often reuses and expands the same nest each year. Pairs are territorial and nests are usually spaced widely apart, especially in higher quality habitats.
Diet and Hunting
The wedge-tailed eagle is an opportunistic predator that eats a variety of prey depending on local abundance. It feeds mainly on medium-sized mammals such as wallabies, small kangaroos and possums. Birds such as parrots, pigeons and ducks are also taken. Wedge-tailed eagles will even attack young lambs and smaller livestock on occasion. They also eat carrion and can often be seen feeding on roadkill. They hunt by soaring high up looking for prey and then swooping down feet first to grab their target in their powerful talons. Pairs sometimes hunt cooperatively to take down larger prey.
Breeding
Wedge-tailed eagles breed in the winter and spring between June and October. They build a large stick nest lined with leaves up to 15 meters high in a tree fork. The female lays 1-3 eggs which are incubated by both parents for around 45 days. The chicks hatch covered in white down and relying on their parents for food and protection. They grow quickly and are able to leave the nest at around 3 months old but continue to be fed by their parents for several more months as they learn to hunt. Young wedge-tailed eagles are dark brown all over and gradually gain their adult plumage as they mature over 4-6 years.
Chainsaw Call
The most distinctive feature of the wedge-tailed eagle is its bizarre ability to mimic the sound of a chainsaw. When threatened or defending a nest, the birds make a startlingly accurate rendition of a chainsaw motor turning over and revving up to full speed. The sound is made vocally and amplified by the bird opening its beak wide. This strange call carries for kilometers and is often the only sign that a pair of wedge-tailed eagles is nesting in the area. The purpose of the chainsaw call is likely to scare away potential predators and warn other wedge-tailed eagles to stay away from the nest site.
Threats and Conservation
Wedge-tailed eagle populations declined historically due to habitat loss and persecution by farmers who blamed them for killing livestock. The use of the pesticide DDT also caused catastrophic egg shell thinning that severely affected breeding success. However, the banning of DDT and protection under the National Parks and Wildlife Act in the 1970s allowed wedge-tailed eagle numbers to recover. They now have a wide distribution across Australia and a population estimated at between 10,000-100,000 breeding pairs. The wedge-tailed eagle is classified as Least Concern on the IUCN Red List.
Significance to Indigenous Australians
The wedge-tailed eagle features prominently in the culture of many Indigenous Australian groups. Known as the eaglehawk, this species is sacred to the peoples of central Australia and appears in traditional ceremonies, rituals and artwork. Archaeologists have found wedge-tailed eagle feathers in Aboriginal cave sites over 40,000 years old. Many creation stories tell of the wedge-tailed eagle’s role in shaping the landscape and determining tribal boundaries. This majestic bird maintains great cultural significance for Indigenous Australians to this day.
Conclusion
The bizarre chainsaw-like call of the wedge-tailed eagle is one of the more unusual and fascinating aspects of Australian wildlife. This massive bird of prey is Australia’s largest raptor and fills an important ecological niche as a top predator. While the chainsaw call may seem unsettling when heard echoing through the bush, it is simply the sound of one of Australia’s most iconic and culturally significant birds defending its territory and young.