Population trend of feral camels in the Northern Territory, AustraliaGlenn P. Edwards A C , Keith Saalfeld B and Bretan Clifford A
A Department of Infrastructure, Planning and Environment, PO Box 2130, Alice Springs, NT 0871, Australia.
B Department of Infrastructure, Planning and Environment, PO Box 496, Palmerston, NT 0831, Australia.
C Corresponding author. Email: firstname.lastname@example.org
Wildlife Research 31(5) 509-517 https://doi.org/10.1071/WR03073
Submitted: 11 August 2003 Accepted: 20 April 2004 Published: 13 December 2004
We conducted a broad-scale aerial survey between 20 August and 12 October 2001 to ascertain the distribution and abundance of feral camels in the southern part of the Northern Territory. There was a minimum of 80 533 feral camels in the Northern Territory at the time of the survey. This figure is corrected for perception bias (a result of observers missing animals that are potentially visible), but not for availability bias (a result of some animals being concealed from the observers). The population of feral camels in the Northern Territory increased at a mean annual exponential rate, r, of 0.093 between 1993 and 2001. This represents an increase of ~10% per year or an approximate doubling in population size every 8 years. This trend is likely to continue for the foreseeable future. We use the results of an earlier survey (which included the Northern Territory, South Australia and Western Australia) to give a minimum figure of 300 000 feral camels for Australia in 2001. We discuss what is known of the impacts of feral camels in Australia, the inadequacy of current management practices and issues to be considered in designing an effective long-term management strategy for the species.
We thank our pilots Tony Spring and Matthew Johnson for superlative flying. We thank Kurt Tschirner, Shane Wright, Bernie Shakeshaft, Jonathan Vea, Simon Watkinson, Jeff Turpin, Kym Schwartzkopff and Salima Spring, who assisted as observers. We sincerely thank Debbie and Matthew Braitling of Mt Doreen station, Ashley Severin of Curtain Springs station, Paula and John Kilgariff of Erldunda station, Peter and Robbie Bloomfield of Andado station, and Kim and Shane Braitling of Numery station for allowing us to use their properties as bases of operation and for their kind hospitality. Rossy Bryan assisted with survey design and logistics. Birgit Dörges, Jurgen Heucke, Ken Johnson, Tony Bowland, Rob Taylor, David Lawson and Tony Pople commented on drafts of this paper. Comments by an anonymous reviewer greatly improved the manuscript. Rainfall data were obtained courtesy of the Australian Bureau of Meteorology.
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