Conventional fencing methods are effective in excluding or retaining livestock but they are not always practical, can be expensive and require on-going maintenance. They can compromise livestock / grassland management or conservation grazing.
While temporary electric fencing may be more flexible it can be time consuming to use nor practical or cost-effective in many areas. Development of a virtual fencing system has the potential to reduce the need for physical stock-proof field enclosures.
Virtual fencing systems
A large body of research over the last 20 years has helped the development of cost effective commercial systems, but as yet these are not quite there. The current most likely system will involve:
on the animal - a neck collar with integrated negative electric stimuli capability, a Global Navigation Satellite System (GNSS) receiver, and a controller linked to cloud computing via a communication module
in the cloud – a management system that links the animal to the manager
in the hand/laptop of the manager – capability to manage the virtual fence line and observe the locations of the animals through a visualisation system.
1. GNSS satellite array provides geolocation to sheep collar
2. Inertial Measurement Units (IMU) data condensed on collar
3. Combined data send to LORAWAN gateway network
4. Then to 'Cloud' and The Things Network and IBM Watson
5. Data analysed and important information to smartphone
6. Farmers gets alert, or checklist or to-do lists
7. Acts upon information
SRUC has conducted applied research on different components of the virtual fencing systems and been heavily involved in developing the thinking of the area.
SRUC has researched the effectiveness of a partial virtual fencing to understand how a full system would work.
The ‘invisible fence’ used cow collars, a battery based transformer and an induction cable laid on or buried in the ground. Each cow was fitted with a device that emits warning sound and negative electric stimuli. Global Positioning System (GPS) collars and activity meters were also used to monitor the effectiveness of the technology.
In a full virtual fencing system, it is vital to have the means to locate livestock by GPS. SRUC has developed its research to track livestock on a ‘live system’ using GPS collars linking by wireless technology to mapping software. Previously GPS location data was held on the collar until the animal was caught and the data downloaded.
The results showed that cattle can be managed using negative electric stimuli collars to create a virtual barrier. Other work using Irritating sounds have an impact but were less effective. Even the visual cue of the deactivated cable during the final control phase was sufficient to deter animals from entering the exclusion area. This shows cattle can also learn from the system.
Applications include ‘virtual paddocks’ to optimise grazing management in both inbye and hill environments, holding cattle location in the right place or away from hazards or exclusions (gorges, bogs, neighbours land, water margins), even a slow and steady ‘gather’ as a virtual fence line is pulled in.
The evolution of virtual fences: A review. Christina Umstatter 2011
Cattle Responses to a Type of Virtual Fence. Christina Umstatter, Justin Morgan-Davies, Tony Waterhouse 2015
Can the location of cattle be managed using broadcast audio cues? Christina Umstatter, Sarah Brocklehurst, David W. Ross , Marie J. Haskell 2013