Sustaining the rock-dwelling macropods of the wet-dry tropics: ecology, conservation and management

A project undertaken at the Key Centre for Tropical Wildlife Management, Northern Territory University, Darwin, and supervised by W Telfer and T Griffiths

The Nabarlek (Petrogale concinna), Short-eared Rock-wallaby (P. brachyotis) and Black Wallaroo (Macropus bernardus) are macropods that inhabit the rocky escarpments and outcrops of the wet - dry tropics of the Northern Territory. The presence of these species, together with the Northern Wallaroo (Macropus robustus ssp. woodwardi), represents an unusually high diversity of sympatric rock-dwelling macropods compared to the rest of Australia (Maynes, 1989). This raises interesting questions about their use of habitats and the scale at which sympatry occurs.

Virtually nothing is currently recorded about the ecology of the species, and their taxonomy and conservation status remain unclear (Eldridge, 1997; Woinarski, 2002). In contrast, Aboriginal communities in northern Australia have a large body of knowledge about macropods on their country. Kangaroos and wallabies have great cultural significance for Aboriginal peoples and many traditional management practices, particularly involving the use of fire, relate to management of land for kangaroos (Altman, 1987; Bowman et al., 2001). Thus there is an opportunity to incorporate Aboriginal knowledge and scientific methods to understand more about this unique fauna group.

Project objectives

A project to describe aspects of the ecology of these species is being conducted by Wendy Telfer, Tony Griffiths and David Bowman of the Key Centre for Tropical Wildlife Management, Northern Territory University, and collaborating with Mark Eldridge of Macquarie University. The specific objectives of the project are to:

  • produce a habitat and distribution model for the species at regional and local scales;
  • determine the consequences of these distributions on long-term population dynamics such as dispersal rates and genetic variability;
  • investigate the habitat use of the species including their diet and home range;
  • record indigenous knowledge of the species and related management practices; and
  • make management recommendations to promote conservation of the species.
Using scats to understand biogeography, diet & habitat use

Surveys are being conducted in rocky country to look for scats (faeces) of the species and record habitat details where each species is found. This information will be used to develop a habitat and distribution model and to understand the scale at which sympatry is occurring.

In order to identify scats found in surveys a key to the scats of the macropods of the Top End has been developed. A field experiment quantifying the persistence and degradation of scats is underway, which will assist with aging scats found in surveys. A reference collection of the cuticles of plant species has also been prepared so that the diet of the macropod species can be analysed.

Trapping, tracking and recording indigenous knowledge

Pilot studies have shown that Short-eared Rock-wallabies demonstrate high levels of vigilance in response to observer presence. Therefore radio-telemetry will be used to give more accurate information about their use of habitats, movements and home ranges. Initial trapping trials for radio telemetry and the collection of tissue samples for genetic analysis have been successful.

We have also been working with communities in Arnhem Land to record their knowledge of the ecology of these species. We are focussing on recording information about the plants eaten by the species, their behavioural habits and distributions.

Project Outcomes

This project will increase our understanding of the ecology of the rock-dwelling macropods of the Top End. This information is required for decision-making about management practices that affect the conservation of the species. Importantly, this project will also assist in the development of management programs that incorporate both indigenous and scientific knowledge. Information required for clarification of the status of the Nabarlek and Black Wallaroo will be provided, as will future monitoring techniques for the species.

References

Altman JC (1987) Hunter-Gatherers Today: An Aboriginal Economy in North Australia. Australian Institute of Aboriginal Studies, Canberra.

Bowman DMJS, Garde M, Saulwick A (2001) Kunj-ken makka man-wurrk, Fire is for kangaroos: interpreting Aboriginal accounts of landscape burning in central Arnhem Land. In: Histories of Old Ages, Essays in honour of Rhys Jones. (ed. OÇonnor S). Pandanus Books, Research School of Pacific and Asian Studies, Australian National University, Canberra.

Eldridge MDB (1997) Rock-wallaby conservation: essential data and management priorities. Proceedings of the 1994 National Rock-wallaby Symposium Workshop. Australian Mammalogy 19, 325-330.

Maynes GM (1989) Zoogeography of the Macropoidea. In: Kangaroos, Wallabies and Rat-kangaroos (ed. Hume I), pp. 47-66. Surrey Beatty & Sons Pty Ltd, New South Wales.

Woinarski JCZ (2002) Threatened Species of the Northern Territory, Information Sheets. Parks and Wildlife Commission Northern Territory, Darwin.

Web site

School for Environmental Research (formerly Key Centre for Tropical Wildlife Management) web site www.cdu.edu.au/ser

 

Logo of the Key Centre for Tropical Wildlife Management

Black Wallaroo

Nabarlek

Short-eared Rock-wallaby

A typical rocky outcrop, Litchfield National Park

Measuring our field experiment on the persistence of scats