Updated information to that provided in Rangelands 2008 - Taking the pulse
Department of Sustainability, Environment, Water, Population and Communities, 2011
About the report
Grazing pressure exerted by domestic livestock (sheep and cattle), kangaroos and feral herbivores (goats, donkeys, camels, rabbits etc) is a major driver of change in the rangelands. The cumulative effect of all grazers in an area is ‘total grazing pressure’ (TGP). In Rangelands 2008 - Taking the pulse (Bastin et al. 2008), ACRIS demonstrated that there are reasonably extensive and reliable data for livestock and kangaroo densities in much of the pastoral rangelands (livestock density updated here, recent regional kangaroo densities reported in a separate document).
Key points to emerge from updated reporting of livestock density include:
- ACRIS now has an embedded process for reporting change in livestock density based on periodic census and surveys of graziers by the Australian Bureau of Statistics (ABS) to obtain stock numbers. These data are processed for ACRIS by the Queensland Department of Environment and Resource Management (DERM). ACRIS is not able to quantify the reliability of all regional data; available jurisdictional data agree for some regions and differ elsewhere.
- Since our previous reporting in Rangelands 2008 - Taking the pulse, stock density (almost exclusively cattle) has continued to increase in many northern pastoral bioregions. Much of this increase is presumed to be driven by continuing strong demand, until 2009, for live-export cattle into south-east Asia.
- In contrast, regional livestock densities declined between 2004 and 2008 in much of the south eastern, southern and south western rangelands.
- Through the first decade of the 21st century, there has been a variable relationship between change in livestock density and seasonal quality (as indicated by decile rainfall). Stock densities appeared to broadly track seasonal quality in some bioregions (i.e. the expected result) while in others (particularly parts of northern and central Australia), density remained above the 1984-91 base as seasonal quality declined.
- Timely monitoring of landscape function and critical stock forage is critical where reduced stocking density does not closely align with declining seasonal quality.
As reported in Rangelands 2008 - Taking the pulse (Bastin et al. 2008), the reliability of findings remains an issue. Reliability of the ABS survey data is unknown where corresponding jurisdictional data are not available for corroboration. Additionally, concordance procedures between Statistical Local Areas (SLA) used by ABS to collate data and bioregions (used by ACRIS for reporting) may be tenuous for those pastoral bioregions where there is small sample size and/or poor spatial correspondence between the two regionalisations.
Kangaroos contribute significantly to total grazing pressure and recent changes in their regional populations are reported in the associated product “ACRIS Kangaroo Density Update 2004-2008”. Continuing lack of quantitative data on numbers of feral herbivores (particularly goats) prevents ACRIS from comprehensively reporting change in total grazing pressure in the rangelands.