Applying virtual fencing technology for grazing and crop management: three case studies with cattle in southern Australian mixed farming systems

Abstract

Context: Advancements in agricultural technologies for animal management such as virtual fencing have applications in crop–livestock mixed farming systems. Targeted control of grazing cattle could, for example, improve weed management or optimise groundcover to mitigate erosion risk. Aims: This research applied the pre-commercial eShepherd® virtual fencing technology to manage cattle on commercial crop–livestock farms in South Australia across three case studies. The success of the technology was assessed against cattle containment, and the impact on the pasture biomass and weeds. Methods: Using different mixed farming paddocks across two farms, three separate trials were run within three separate years on different groups of cattle (n = 20, 40, and 35 cattle for the three trials respectively), with the implementation of the virtual fence becoming more complex across the trials. Animal movement and behaviour were monitored using the technology to evaluate the effectiveness of virtual fences in restricting animals during grazing. In two of the three trials, a control cohort of cattle was included in a separate part of the paddock (n = 20 and 25 cattle respectively). Pasture/crop biomass measures and weed assessments were also performed at each trial. Key results: Across the different paddock contexts, the virtual fence successfully restricted cattle to specified areas for most of the trial time. This facilitated targeted grazing for weed control, while avoiding over-grazing. The animals all learnt to respond to the audio cue alone. There were inconsistent impacts of virtually fenced grazing relative to control grazing on biomass cover, which were likely to be driven by combinations of grazing pressure, soil variations and pasture growth. Conclusions: The trials have demonstrated applications of strip grazing, strategic exclusion from vulnerable areas with enhanced grazing on remaining areas of paddocks and targeted heavy grazing for weed control within commercial cropping paddocks. The trials complement the growing number of virtual fencing studies assessing animal behaviour and impacts on pasture growth when grazing can be better controlled. Implications: In the Australian crop–livestock system context where sheep are more common than cattle, these results with cattle also point to the potential applications and advantages if cost-effective virtual fencing technology can be developed for sheep.