What is virtual fencing (or virtual herding) and does it impact animal welfare?

What is virtual fencing?

Virtual fencing aims to remotely map and control livestock grazing behaviour without the use of fixed fences [1]. This technology, which was first developed in 2005, uses Global Positioning System (GPS) sensors and wireless technologies to control the movement and location of animals within an area [2].

How does virtual fencing work?

For virtual fencing to work, animals need to be fitted with a GPS collar. The collar emits a tone (audio cue) and an electric shock. As the animal approaches a pre-determined virtual barrier, the GPS collar emits an audio cue (a single continuous tone at 785 Hz ± 15 Hz). If the animal continues towards the virtual barrier, the animal receives an aversive electric shock – in cattle, this is usually 800 Volts delivered in less than 1 second [3, 4]. This requires animals to respond appropriately to the audio cue (i.e. move in a different direction) to avoid receiving an electric shock. Although the method of delivery of the electric shock is not directly comparable to that of an electric fence, the intensity of the shock delivered by the collar worn by cattle is less than that of an electric fence [5]. For sheep, the studies used a modified and manually operated shock collar for dogs which could deliver an audio cue as well as administer a 320 Volts electric shock [6].

Virtual fencing has the potential to improve livestock, pasture and environmental management and reduce labour and costs associated with fixed fences. However, the use of electric shocks to train an animal raises significant ethical and animal welfare concerns. For example, what are the potential welfare implications to animals who don’t understand and are unable to learn quickly? Or for animals who never learn? Are there implications on animals’ mental state?

What are the animal welfare implications of virtual fencing?

Although there are claims that virtual fencing is an animal-friendly technology [2] that meets high animal welfare standards, there is a lack of research regarding the long-term impacts of this technology on animal welfare.

One of the main welfare concerns of virtual fencing is the use of an electric shock, which has been shown to produce an acute stress response in animals [7]. In addition, pain, aversion and chronic stress may occur [1]. Farm animals find handling and husbandry procedures stressful, too, and studies have found that an electric shock elicited a similar stress response to that in cattle being restrained in a crush or to sheep hearing a barking dog [8, 9]. One experiment, found no significant behavioural differences between small groups of cattle confined behind a virtual fence or an electric tape fence [5].

Another welfare concern of this technology is that it initially exposes animals to an environment of low predictability and controllability, which can lead to anxiety and stress [4]. During the initial phase of training, animals do not know what the audio cue means, and therefore cannot avoid receiving the electric shock(s) [4]. During the learning and adaptation phase, animals may be in an aroused state and experience stress for several hours to several days until they have learnt to link the audio cue with the electric shock and understand how to respond, i.e. move away, in order not to receive a shock [10]. Learning is successful when an animal is able to predict and control how they interact with the virtual fence.

As the virtual fence is not visible, it may be more difficult for some animals to learn as there are no visual cues to guide them. Studies have reported that cattle learn to respond to the audio cue after 4-6 electric shocks, but high individual variation has been observed in animals’ rates of learning [11, 3]. A more recent study showed that cattle need around 2.5 interactions with the virtual fence (i.e. electric shocks) before moving away upon hearing the audio cue [5]. The virtual herding project’s final report mentions that across many of the trials, once animals were trained, nearly 90% responded to the audio cue and avoided receiving an electric shock. This suggests that some animals may learn much slower or may not learn at all, putting them at a higher risk of compromised welfare. Animals with prior exposure to an electric fence appear to learn to respond faster to the audio cue [12]. Social learning also appears to play a role, with both cattle and sheep in small experimental groups following a herd mate who they’d seen move away from the virtual fence [13, 14]. Further studies are needed to investigate the long-term effects of virtual fencing on the physiological and behavioural response of animals.

Other welfare concerns of virtual fencing relate to potential irritation and/or ulceration of the skin due to the use of collars, choking on collars and equipment malfunction [1].

What laws control the use of virtual fencing in Australia?

State and territory animal welfare legislation determines where and what type of electronic devices can or cannot be used to contain livestock. The electronic collars have been trialled on farms in Queensland, New South Wales and Tasmania as part of the Department of Agriculture and Water Resources Rural Research and Development for Profit Program (see here for more information and the final report). Currently, the collars are not commercially available in Victoria, South Australia, Northern Territory and the ACT. However, exemption permits can be obtained for research purposes. In Victoria for example, electronic collars can be used on cattle, sheep, goats, pigs, camels, alpacas or llamas as part of a scientific procedure, or a program of scientific procedures, approved under a licence granted under Part 3 of the Prevention of Cruelty to Animals Act 1986. In the Northern Territory, an exemption to the Animal Welfare Act allows cattle to be fitted with the collars and trials of the technology to take place. In Western Australia, the Animal Welfare (General) Regulations 2003 were changed in June 2022 and now permit the use of virtual fencing technology as long as the device is used in accordance with the manufacturer’s instructions.

What is the RSPCA’s view?

The RSPCA is opposed to the use of electronically activated devices that deliver an electric shock to animals, as these are aversive. RSPCA supports the use of humane husbandry and management practices that do not cause pain, injury, suffering or distress. Where virtual fencing technology is legally permitted, the use of collars should be subject to regulation that ensures safeguards are in place to protect the welfare of animals. This includes adherence to standards that ensure appropriate use and avoid animal harm as well as third-party monitoring/auditing to verify compliance.