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Powerful Owls: Possum Assassins Move into Town

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Urban Raptors

Abstract

Once thought to live only in large forested areas, the powerful owl (Ninox strenua), Australia’s largest and most iconic of owls (figure 11.1), surprisingly is now turning up frequently in the cities of eastern Australia. Powerful owls require ample prey and large tree cavities for nest sites; how this top-order predator is able to survive in human-dominated landscapes is an important question for conservation and the focus of ongoing research. The powerful owl is endemic to Australia, resident in the three eastern mainland states and the Australian Capital Territory, and classified nationally as “rare.”2,3 First described by Gould in 1838, powerful owls are an unusual raptor in that they do not exhibit reversed sexual size dimorphism, the prevalent trait among raptors in which females are larger than males. For reasons still not understood, male powerful owls grow to a height of 65 cm and weigh up to 1,700 g, compared to females, which grow to a height of 54 cm and weigh up to 1,308 g.1

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© 2018 Cheryl R. Dykstra

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Cooke, R., Hogan, F., Isaac, B., Weaving, M., White, J.G. (2018). Powerful Owls: Possum Assassins Move into Town. In: Boal, C.W., Dykstra, C.R. (eds) Urban Raptors. Island Press, Washington, DC. https://doi.org/10.5822/978-1-61091-841-1_11

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