Long-term burning: Cadell River

By Jeremy Russell Smith, Bush Fires Council of the NT & Tropical Savannas CRC
from Savanna Burning — Understanding and Using Fire in Northern Australia, Tropical Savannas CRC, 2001

A key question concerning the traditional use of fire is the long-term impact this has on plants and animals. In much of northern Australia this question can no longer be addressed given the cessation of traditional modes of management.

However, in 1997 an assessment of the ecological effects of an essentially unbroken tradition of burning was undertaken on a clan estate (i.e. country belonging to one family group) on the upper Cadell River in central Arnhem Land. The project was undertaken as a collaborative ranger training exercise between the Bawinanga Association and the Parks and Wildlife Commission of the Northern Territory.

Traditional burning practice on this clan estate includes lighting mostly small fires throughout the year, and cooperating with neighbouring clans in planning and implementing burning regimes. The assessment was undertaken over 10 days in September after prescribed burning had mostly been completed.

Ecological assessment

Ecological assessments included: mapping of the resource base of the estate from both traditional and ecological perspectives; aerial survey of the extent ofburning, distribution of fire-sensitive cypress pine, rock habitats, and a range of kangaroo and other animal resources; animal inventory; detailed ecological assessment of the status of fire-sensitive vegetation; and on-ground assessment of the intensities of observed fires. As well, ethnographic information concerning traditional fire management practice was documented in interviews with senior custodians.

Major observations included:

• A large proportion of the estate had been burned during the year of study.
• Resultant fires had been almost invariably patchy and of low intensity given that fuel loads comprised mostly leaf litter and little grass.
• Burned sites attracted important animal food resources such as large macropods.
• Important plant foods remained abundant.
• Fire-sensitive communities were well represented (e.g. cypress pine woodlands, sandstone heath, riparian rainforest communities).
• exotic plants were not recorded.
• diversity of vertebrates and fire-sensitive plants was high, including rare or range-restricted species.

Conclusions

The above assessment provides a rare insight into the long-term effects of traditional burning. Certainly, the particular clan estate was shown to be in better shape than many other comparable areas in northern Australia where, today, fire regimes are dominated by extensive, typically intense fires burning mostly grassy fuels. The assessment shows the value of intensive fire management over a relatively small area (about 90 sq. km), but there are obvious logistical difficulties when applying such fine-scale management over larger areas.

Further, despite evident differences in purpose between traditional indigenous and contemporary fire management practice, this assessment shows that outcomes from well and consistently executed traditional practice can be consistent with many widely shared land management and conservation goals.