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RESEARCH ARTICLE
Contents Vol 56(4)

Movements and distribution of dugongs (Dugong dugon) in a macro-tidal environment in northern Australia

Scott D. Whiting
+ Author Affiliations
- Author Affiliations

Faculty of Education, Health and Science, Charles Darwin University, NT 0909, Australia. Current address: Department of Natural Resources, Environment and the Arts, PO Box 496, Palmerston, NT 0830, Australia. Email: scott.whiting@nt.gov.au

Australian Journal of Zoology 56(4) 215-222 https://doi.org/10.1071/ZO08033
Submitted: 26 March 2008  Accepted: 2 October 2008   Published: 22 December 2008

Abstract

A combination of aerial surveys, community sightings and satellite tracking revealed distribution, habitat, relative densities and spatial use of individual dugongs in the Darwin region of the Northern Territory. Aerial surveys in both the wet and dry seasons estimated relatively low densities of dugongs. Most group sightings (73% of all sightings) and densities up to 0.54 dugongs km−2 occurred in one of the four blocks surveyed. This block contained the Vernon Islands and large macro-tidal algal rocky reefs. Two dugongs tracked using satellite transmitters were captured above these reefs and kept a close association with similar reef types during most of their tracking periods of 53 and 154 days. Tracking revealed that dugongs used multiple and distinct areas for periods of several days to over 80 days and utilised coastal sections of up to 300 km in length. This indicates that dugong management in the Darwin region requires the consideration of large spatial scales, multiple habitat types and rocky reef habitat. Community sightings were an important information source and revealed locations of dugongs not identified with either the aerial surveys or satellite tracking.


Acknowledgements

This study was funded by Coast and Cleans Seas (Natural Heritage Trust – Australian Government, 2001–2002). This project was made possible by the input from consortium members: Larrakia Nation, Belyuen Community, Conservation Volunteers Australia and the Parks and Wildlife Commission of the Northern Territory. This research was conducted with Animal Ethics Approval (Charles Darwin University) and under a research permit from Parks and Wildlife Commission of the Northern Territory. Keith Saalfeld provided advice on analysis of the aerial survey data. Special thanks to individuals who contributed to the project: Dr Michael Guinea, Chris Jones, Donna Jackson, Yasmin Alley, Tanya Panvel, Charlie Tapin, Chandra Salgado, Andrea Whiting, Dale Hardy, Simon Gummer, Erin Britton, Jessica Seemann, Juliette Labaronne and Kate Goodrich. The supply of aerial survey equipment by Dr Bob Prince, DEC, WA, was greatly appreciated. Promotion of this project was conducted by ABC Radio, NT News, Darwin and Palmerston Sun, Marine and Coastal Community Newsletter and the NT Field Naturalists Newsletter. Preliminary work was supported by The Power and Water Authority, Darwin. Ivan Lawler, Barry Russel and Andrea Whiting made valuable comments to this manuscript.


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