Spatial ecology of Sooty Owls in south-eastern Australian coastal forests: implications for forest management and reserve design
Rohan J. Bilney A , John G. White A , Felicity A. L’Hotellier A B and Raylene Cooke A C
+ Author Affiliations
- Author Affiliations
A School of Life & Environmental Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia.
B Scotia Sanctuary, via Wentworth, NSW 2648, Australia.
C Corresponding author. Email: raylene.cooke@deakin.edu.au
Emu 111(1) 92-99 https://doi.org/10.1071/MU09069
Submitted: 31 July 2009 Accepted: 30 June 2010 Published: 21 February 2011
Abstract
We investigated the home-range size and habitat use of eight Sooty Owls (Tyto tenebricosa tenebricosa) in coastal forests in East Gippsland, Victoria, Australia, between November 2006 and January 2008. The size of home-ranges varied widely; based on 95% adaptive kernel estimates, the average size of home-ranges of males was 3025 ha (±1194 s.d., n = 3), whereas that of females was 994 ha (±654 s.d., n = 5). Sooty Owls utilised a broad range of ecological vegetation classes and topographical features for roosting and foraging at a greater scale than previously assumed. There was minimal selection for habitat types based on floristic composition, primarily only avoiding heathlands (for foraging and roosting) and selecting particular dense foliage (rainforest and riparian scrub) for foliage roosting. Two Owls maintained home-ranges close to logged areas, with logging regrowth (<45 years old) being strongly avoided by both individuals. We recommend that the size of individual reserves for Sooty Owls in commercial forests should be increased to more closely resemble the core spatial resource requirements needed by a pair. Reserves should be largest where they feed predominantly on hollow-dependent prey. Most importantly, rather than conservation measures just focussing on the spatial requirements of Sooty Owls, efforts should be directed towards retaining high densities of crucial resources, such as hollow-bearing trees and mammalian prey species throughout the landscape.
Additional keywords: habitat use, hollows, home-range, logging, Tyto tenebricosa.
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