Substantial investments have been made into constructing pest-proof netting fences (‘cluster fences’) around multiple grazing properties in western Queensland. Effective control of many vertebrate pests (e.g. wild dogs, kangaroos, feral pigs and feral goats) is now possible across large areas, by denying immigration, offering widespread and substantial benefits to agriculture and the environment. Similar fences are proposed for more arid areas in southern rangelands of WA, but the optimal cluster size and likely benefits for particular land types and production systems are unknown. This project brings together and expands the scope of existing studies to inform future cluster fencing activities.
In the Morven region, weather conditions have been very dry, resulting in poor pasture conditions. Pasture dry matter is being monitored inside and outside the Morven cluster. Prior to closure of the cluster fence, pasture biomass was higher outside, but that difference is less now.
Since the Morven cluster was closed in 2015, the number of wild dogs captured inside the fenced area has declined rapidly. Contract trappers removed 16 wild dogs from within the Morven cluster during 2018. A total of 523 wild dogs have been trapped and destroyed since fence construction commenced.
Wild dog activity across multiple properties in the Tambo cluster shows the expected annual breeding peaks in activity in autumn but there is an encouraging underlying trend of a gradual reduction over time inside the cluster. This suggests producers or sub-clusters are making incremental progress at removing this problem species.
The estimated abundance of kangaroos inside and outside of the Morven cluster has declined substantially since August 2017. The pattern for kangaroo density at Tambo is similar to that found in Morven with consistently higher densities inside the clusters than outside. This is attributable to the combined impacts of drought, predation and less productive land being located outside clusters.