Imaginary fences that stop cattle in their tracks are being used by rangers to control grazing on Ashdown Forest in Sussex.
Cows are fitted with solar collars that emit a sound and mild electrical pulse. It persuades them to turn back from the virtual boundary lines that have been generated using GPS.
Ashdown Forest is among the first areas in the UK to work with the pioneering technology.
It means cattle can graze freely over areas that weren't previously possible to physically fence and rangers can use their mobile phones to check on the animals.
The “NoFence” system has enabled Forest Rangers to protect areas of land during the recent breeding season of ground nesting birds including the endangered nightjar.
Ash Walmsley Ashdown Forest’s Countryside Manager said: "The cattle learn very quickly, meaning when changes are made to the virtual fence line the sound is usually all that is needed to turn them round and the herding instinct means the others will follow.
"If we need to change the boundaries, we can do it quickly and remotely. It has been a fantastic addition to our conservation grazing here on the Forest.
“This great mix of hi tech and natural instincts is helping to manage this precious landscape and maintaining access to everyone."
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know...