The posts are covered in a perfumed oil that attracts deer. But when the deer touch the post, they are zapped by a harmless shock that frightens them away. Deer rely heavily on their sense of smell for their safety, said Dr. Keith Betzen, a veterinarian who developed the product.
Fear is also a motivator.
Deer associate the scent of the perfumed oil with the discomfort of the shock and will not return to the area, he said. The shock feels like static electricity. The posts recharge themselves every 12 minutes, eliminating the possibility of repeated shocks. However, the energy delivered is so slight that it will not harm anyone who accidentally touches the post, Betzen said. Each post operates on two AA batteries.