ABSTRACT
We deployed satellite transmitters to provide the first detailed picture of the movement behaviour of Australian Wood Ducks (Chenonetta jubata) through agricultural landscapes where the availability and spatial arrangement of resources are highly predictable. We measured movement distances and home-range areas of individual Australian Wood Ducks and investigated their site fidelity by comparing the overlap of successive home-range areas on a fortnightly temporal scale. First passage time (FPT) analysis was used to determine the spatial scales at which foraging occurs within home-range areas. We found a peak of movement activity around the periods of dawn and dusk similar to many waterfowl species. The mean overlap of core home-range areas over successive 2 week periods was 89.81% (± 2.38 SD), which demonstrates strong site fidelity. Area-restricted search (ARS) occurred at the scale of individual foraging (ca.100 m), with no clear peaks at larger spatial scales. This finding implies that search effort was expended equally across the combined utilisation distribution of Australian Wood Ducks in this agricultural landscape. Our results support the conclusions of previous studies suggesting that the movement behaviour of Australian Wood Ducks is shaped strongly by the temporal and spatial predictability of their grazing areas and access to water in the form of farm dams.
Acknowledgements
This work was carried out under scientific permits from the New South Wales Office of Environment and Heritage (licence no. SL101457) and was approved by the University of New England Animal Ethics Committee (authority no. AEC14-104). We are indebted to the National Parks and Wildlife Service, NSW. We are grateful to a number of people for their assistance with fieldwork: Koen Dijkstra, Milla Mihailova, Ahmad Barati, Louise Streeting, Sigrid Mackenzie and Alice Bauer. The study was funded by the New South Wales Department of Primary Industry Game Licensing Unit through a grant provided to P.M. and G.H. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
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