1. New South Wales Department of Primary Industries, Fisheries Conservation Technology Unit, PO Box 4321, Coffs Harbour, NSW 2450, Australia
2. School of Mathematics and Applied Statistics, Faculty of Informatics, University of Wollongong, Wollongong, NSW 2522, Australia
3. Quantitative Biosciences: Mathematics, Informatics and Statistics, CSIRO, Canberra, ACT, Australia
4. School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia