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Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

The diet of powerful owls (Ninox strenua) and prey availability in a continuum of habitats from disturbed urban fringe to protected forest environments in south-eastern Australia

R. Cooke A D , R. Wallis B , F. Hogan A , J. White A and A. Webster C
+ Author Affiliations
- Author Affiliations

A School of Life and Environmental Sciences, Deakin University, Burwood Campus, 221 Burwood Highway, Burwood, Vic. 3125, Australia.

B Office of the Pro-Vice-Chancellor (Rural and Regional), Deakin University, Warrnambool Campus, Warrnambool, Vic. 3280, Australia.

C Department of Sustainability and Environment, Box Hill, Vic. 3128, Australia.

D Corresponding author. Email: raylene.cooke@deakin.edu.au

Wildlife Research 33(3) 199-206 https://doi.org/10.1071/WR05058
Submitted: 30 June 2005  Accepted: 16 March 2006   Published: 31 May 2006

Abstract

This study investigates the diet of six breeding pairs of powerful owls in the Yarra Valley Corridor in Victoria, Australia, and compares prey consumption with prey availability. The six sites represent a continuum of habitats, ranging from urban Melbourne, through the urban fringe interface to a more forested landscape. We found that powerful owls in the Yarra Valley Corridor are reliant almost exclusively on arboreal marsupial prey as their preferred diet, with 99% of their overall diet comprising four arboreal marsupial species. These four species (the common ringtail possum, common brushtail possum, sugar glider and greater glider) were also the most abundant species observed while spotlighting; however, their abundance varied along the continuum. There was a strong positive relationship with the presence of these species in the diet and their site-specific availability, indicating that the powerful owl is a generalist hunter, preying on the most available prey at a given site and in a given season. This study suggests that food resources are high in these disturbed urban fringe sites and it is unlikely that food availability in urban environments will limit the potential survival of urban powerful owls.


Acknowledgments

We thank the Holsworth Wildlife Research Fund, the M.A. Ingram Trust, Birds Australia, and Deakin University for providing financial support as without such support this research would not have been possible. We also acknowledge the constructive suggestions provided by referees of this manuscript.


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