Circus approximans - Busard de Gould
- Size: 61 cm
- Wingspan: 118 à 145 cm.
- Weight: 500 à 1100 g
Females are larger than males. Adults have a light grey head, cheek, nape and hood. The upperparts all the way to the tail is presents different hues of brown. However the scapulars and the mantle tend toward a rufous-orange colour. The underparts are white with fine brown streaks. The feathers covering the thighs are orange or pale brown. The undertail coverts are grey and slightly barred. The eye is yellow, as are the legs. First-winter juveniles have brown eyes, a dark brown plumage with an obvious white nape. As they get older, the eye and plumage get paler. Some older birds can even appear greyish-white.
Subspecific information monotypic species
- Busard de Gould,
- Aguilucho Lagunero del Pacífico,
- mocsári rétihéja,
- Australische Bruine Kiekendief,
- Albanella australasiatica,
- Australisk kärrhök,
- kaňa barinná,
- moták tichomořský,
- Australsk Rørhøg,
- arpella del Pacífic,
- błotniak moczarowy,
- Болотый лунь,
- Elang-rawa coklat,
The Australasian Harrier is a specialist of open country and sparse vegetation, and is found from sea level to an altitude of 1,200 meters.
Behaviour character trait
All year round, the Australasian Harrier patrols its territory in search of food. It flies over the countryside, circling effortlessly during long hours. It follow air currents, alternating between gliding and beating its wings. It is frequently mobbed by other species, especially the Spur-winged Lapwing which will harass harriers until they turn tail.
Although it capture most of its prey on the ground, this raptor seems to have developed a knack for capturing birds perched at the top of trees or sometimes even in flight.
The long breeding season starts in June, when pairs patrol their territory together to ward off intruders.
The female alone incubates the 1-7 eggs while the male provides her with food for the 31-34 days of incubation. She also feeds the chicks with the preys that the male brings back. When the chicks are old enough both partners hunt and if the male is alone when returning to the nest, he will drop the food in but will not actively feed the chicks. 2-3 weeks later, the young harrier leave the nest and spread out in the nearby vegetation. They will only fly after 45 days, but stay around the nest and call repetedly until one of the adults provides them with food.
Sources of information
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