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Australian Journal of Zoology Australian Journal of Zoology Society
Evolutionary, molecular and comparative zoology

Field metabolic rate and water turnover of red kangaroos and sheep in an arid rangeland: an empirically derived dry-sheep-equivalent for kangaroos

A. J. Munn A D E , T. J. Dawson B , S. R. McLeod C , D. B. Croft B , M. B. Thompson A and C. R. Dickman A
+ Author Affiliations
- Author Affiliations

A School of Biological Sciences, The University of Sydney, NSW 2006, Australia.

B School of Biological, Earth and Environmental Sciences, The University of New South Wales, NSW, 2031, Australia.

C New South Wales Department of Primary Industries, Orange Agricultural Institute, Orange, NSW 2800, Australia.

D Present address: Faculty of Veterinary Science, The University of Sydney, NSW 2006, Australia.

E Corresponding author. Email:

Australian Journal of Zoology 57(1) 23-28
Submitted: 24 July 2008  Accepted: 7 April 2009   Published: 6 May 2009


Sustainable management of pastures requires detailed knowledge of total grazing pressure, but this information is critically lacking in Australia’s rangelands where livestock co-occur with large herbivorous marsupials. We present the first comparative measure of the field metabolic rate (an index of food requirement) of Australia’s largest marsupial, the red kangaroo (Macropus rufus), with that of domestic sheep (Ovis aries; merino breed). We tested the assumption that the grazing pressure of red kangaroos is equivalent to 0.7 sheep, and show this to be a two-fold overestimation of their contribution to total grazing. Moreover, kangaroos had extraordinarily lower rates of water turnover, being only 13% that of sheep. Consequently, our data support arguments that the removal of kangaroos may not markedly improve rangeland capacity for domestic stock. Furthermore, given the low resource requirements of kangaroos, their use in consumptive and non-consumptive enterprises can provide additional benefits for Australia’s rangelands than may occur under traditional rangeland practices.

Additional keywords: marsupial, sustainable grazing, total grazing pressure.


We thank Fowlers Gap (UNSW) and G. Curran (NSW DPI). We thank B. Green and K. Newgrain for discussion of the doubly labelled water method. This project was funded by ARC Grant (LP0668879) to AJM, CRD and MBT in collaboration with the NSW Department of Environment and Climate Change Kangaroo Management Program (N. Payne), the SA Department for Environment and Heritage (L. Farroway), the WA Department of Environment and Conservation (P. Mawson), the NSW Western Catchment Management Authority and the NSW Department of Primary Industries. Ethics approval: UNSW ACEC 06/85A. NSW National Parks and Wildlife Scientific Licence S12054.


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