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Description
The powerful Owl (Ninox strenua) is a shy bird. This bird of prey lives in pairs and keeps to large permanent territories of 800- 1000 hectares. They roost by day, heads erect, in tall forest trees which give them a commanding view of their surroundings.
Each pair has a number of roosting trees and the birds roost on different trees on different days, not always together, but always within calling distance. Till now, this is the only bird that has been known to kill a human being. So that’s why this is called Powerful Owl due to its strength.
Identification
Both adult sexes are similar, but the male bird is a bit larger. The upper parts are dark gray-brown barred with white and pale brown, the barring finer on the crown and coarser on the wings and tail. The face mask is incomplete, dark gray-brown with white streaks. Though, the throat and underparts are creams or pale buff barred with gray-brown chevron-shaped markings.
Also, the eyes are orange-yellow with the bill bone is grey grading to black at the tip; cere bone-grey. Toes are creamy yellow, and claws are dark gray. The immature Powerful owl is similar to adults. However, the downy young are white-downed.
Powerful Owl Call
The mournful woo-hoo call of Powerful Owl may be heard at any time of the year. But the birds are more vocal during the breeding season, predominantly just after dusk and just before dawn. They sometimes begin calling before sunset.
What Does the Powerful Owl Eat?
At night, the Powerful Owl preys on birds and mammals. Its diet consists mainly of small to medium-sized tree-living mammals, especially the Great Glider (Petauroides volans) and the Common Ringtail Possum (Pseudocheirus peregrines). These it snatches from foliage and branches in banking swoops through the forest mid-stage.
It also eats Sugar Gliders (Petaurus breviceps) and, less often, young Common Brushtail (Possums Trichosurus vulpecula). Further, rats, birds, and young rabbits are also taken. It tears its prey apart and eats it by the piece, usually beginning with the head which it often swallows whole.
Sometimes it will take the rear end of the animal back to its roots, carefully place it on the branch and hold it all day in its talons, then eat it before leaving the roost in the evening. The owls need to eat the equivalent of a large possum every two-three days to survive.
Size of Powerful Owl
The size of a Powerful Owl is 610-650 mm in length with a wingspan of up to 140cm and 1.50kg in weight.
Distribution
Powerful Owl distribution is Southeastern South Australia, to Dawson River, near Rockhampton, Qld, mostly in wee sclerophyll forest along coast hills and the Great Dividing Range.
Voice
The voice of Powerful Owl preys on possums and other small mammals. Territorial call, by both sexes, a mournful, loud, slow woo-hoo on the same pitch or slightly rising, with about 10 seconds between each hoot, given through closed bill. Male’s cal/ lower pitched and slower than chat of female. Courting male and female rumble, rasp, and males give pulsating poorp-poorp-poorp. Nestlings beg with a shrill trill.
Nesting and Breeding
The nesting and breeding months are May-October, laying May-early June; one brood a year. The owl builds a nest a 60-185 cm deep hollow 13-40 meters above ground in the trunk of cowering eucalypc, lined with wood debris and prepared by the male.
Eggs
The owl lays two to four pure white eggs that are rounded, 50-50 x about 45 mm. Therefore, the incubation period is about 36-38 days, for females, beginning with the laying of the first egg. Also, the young bird fledges in eight to nine weeks. Females are given food outside the nest by males and passed by her alone co young during brooding.
Related Reading – What Makes Owls So Wonderful
