Virtual fence: New realities beyond barbed wire

• Virtual fence (VF) is an emerging system to control and confine animals using Global Positioning System (GPS) and communication technologies rather than physical boundaries such as barbed wire or electric fence. • Animals in a VF system wear a device (e.g., a collar) that emits an audible cue when the animal approaches the virtual boundary and an electrical cue if the boundary is crossed. • VF provides an adaptive grazing management tool to intensify grazing in some areas or minimize animal use in other areas for specific conservation or production goals. • Several challenges currently exist with emerging VF technologies and include failure of devices, animals that do not respect the boundary, and excessive time and money to implement. • VF promises increased flexibility for managing rangelands in response to ecosystem disturbances such as wildland fire, variable forage availability due to climate change, facilitating restoration practices, reducing conflicts between livestock and wildlife, and accommodating human uses on public lands.