The potential for virtual fencing in mixed farming

Take home messages

• Virtual fencing offers major potential economic and land management benefits for grazing and mixed farming.
• Virtual fencing technology is at the point of commercial availability for cattle, but relatively little work has been done to address the additional challenges of developing the technology for sheep.
• Field testing of virtual fencing methods so far has successfully demonstrated the potential application and efficacy of virtual fencing methods with sheep.

Background

Achieving optimal integration of cropping and grazing remains a major management challenge. As an example, increasing paddock sizes (or in some cases removing fences) to increase cropping efficiency usually reduces the ability to graze efficiently and manage any vulnerable areas. There is potential for sub-paddock fencing to improve both cropping and livestock productivity by managing grazing pressure of pastures, grazed crops and crop residue within cropping paddocks. Being able to avoid excessive grazing pressure on the most vulnerable parts of the paddock could also make grazing more profitable and less risky when meeting the increasing demand for early-season crop grazing to provide winter feed for livestock.

Electric fencing for sub-paddock grazing is rarely used because of the labour, costs and other difficulties associated with managing temporary fences on large mixed farms. The potential for virtual fencing using global positioning system (GPS)-enabled devices which are attached to animals and provide a signal to animals to deter them from grazing in particular areas of a paddock is an attractive option to many farmers. Other potential benefits of spatial grazing include the ability to target grazing on areas of paddocks with high weed levels, reduce grazing pressure on vulnerable areas of establishing pastures, reduce risk of crop yield loss caused by overgrazing vulnerable areas of grazed grain crop, and protect areas for revegetation.

After more than a decade of development, the GPS-based technology to facilitate spatially-targeted grazing using ‘virtual fencing’ is at the point of commercial availability for use with cattle (Campbell et al. 2018; World's FIrst Livestock Virtual Fence). Recent CSIRO trials have tested the potential for virtual fencing methods to be used to manage sheep grazing. As well as conducting the first on-farm trials of their type in NSW and SA, the work has evaluated the potential economic benefits of spatial grazing using virtual fencing in mixed farming.

Results and discussion

Paddock testing

Over the past two years field trials have been conducted to test the potential to manage sheep with virtual fencing methods. Trials were initially conducted at the CSIRO research station near Armidale, NSW to test the ability of individual sheep to be trained to respond to an audio cue on test collars.

The first on-farm trial was conducted near Gol Gol, NSW in 2017 to test whether a small number of sheep can be excluded from an erodible area of a small paddock (Marini et al. 2018). Sheep were successfully kept out of the excluded zone of the paddock. The probability of a sheep receiving an electrical stimulus following an audio cue during the testing period was low (19 %). By the third day the sheep were able to avoid receiving an electrical stimuli by turning away from the boundary when the warning audio was applied. Following the removal of the virtual fence sheep were willing to cross the previous location of virtual fence after 30 minutes of being in the paddock. This is an important aspect in the implementation of virtual fencing as a grazing management tool and further enforces that the sheep in this study were able to associate the audio with the virtual fence and not the physical location itself.

After gaining legislative change to allow trialing of virtual fencing in SA, a trial at Waikerie was conducted in 2018 involving a larger number of sheep and testing how effectively sheep grazing can be managed when not all sheep are wearing a virtual fencing device. As in the previous trial, the virtual fencing method of applying ‘manual’ application of a sound alert followed by electrical stimulus if required, was fully effective. Exclusion from the northern zone was successful for 100% and 66% collared treatments but not the 33% collared treatment. Importantly the trials have demonstrated strong learning responses from sheep through the ethical application of virtual fencing devices. The most recent trials demonstrated the potential for successful grazing management when not all sheep wore a device, but larger scale and longer-term trials with greater grazing incentive are still required.

Figure 1. Residency maps for the flock under each treatment at Waikerie showing successful exclusion from northern zone under 100% and 66% collared treatments.

Making it pay

Increasingly large crop paddock sizes make it difficult to achieve high grazing efficiency while maintaining optimal levels of crop residue on vulnerable areas. The potential economic and production benefit of sub-paddock spatial grazing for mixed farmers has been demonstrated using whole-farm economic analysis (MIDAS) for a low-rainfall mallee-region farm (Llewellyn et al 2017). Based on being able to avoid having to remove livestock from an entire paddock when just one soil or zone incurs excessive groundcover loss, whole-farm income gains of approximately 15% were shown even when cropping still comprised 70-80% of arable land. Importantly, introducing spatial grazing increased the relative profitability of livestock in the system, in some cases doubling the profit maximising stocking rate. Analysis of potential gains through targeted grazing pressure for weed management showed similar paddock-level gains.

Conclusion

Results from several trials demonstrate the ability for sheep to learn to respond rapidly to virtual fencing audio cues and the successful management of sheep grazing using virtual fencing. Further on-farm work on larger scales and over longer time frames is now needed. While GPS-based virtual fencing for cattle is at the point of commercial availability, substantial investment is still required for development of a commercial device adapted for sheep. The large potential grazing management, economic and environmental benefits of virtual fencing for sheep, backed by a high level of farmer demand, offer strong encouragement for the pursuit of this goal.

Acknowledgements

This project is supported by funding from the Australian Government Department of Agriculture and Water Resources and CSIRO.

The trials were conducted in collaboration with Michael Moodie and farmers Bill Barnfield, Graham Paschke and Allen Buckley from Mallee Sustainable Farming with additional support from Jim Lea and Chris Davies.

Initial whole-farm analysis of virtual fencing was part of the GRDC-funded CRC Future Farm Industries EverCrop project (CSA00044). The research undertaken as part of this project is made possible by the significant contributions of growers through both trial cooperation, and the support of the GRDC.

References

Campbell DM, Lea JM, Haynes SJ, Farrer WJ, Leigh-Lancaster CJ, Lee C. 2018. Virtual fencing of cattle using an automated collar in a feed attractant trial. Applied Animal Behaviour Science 200:71-77.

Llewellyn R, Monjardino M, Moodie M, Trotter M, Economou Z. 2017. The potential for spatial grazing and virtual fencing in mixed farming systems. Proceedings Australian Agronomy Conference.

Marini D, Llewellyn R, Belson S, Lee C. 2018. Controlling within-field sheep movement using virtual fencing. Animals. 8:31

Contact details

Rick Llewellyn
CSIRO, Waite Campus, Adelaide
08 83038502
rick.llewellyn@csiro.au