An energizer charges parallel fence wires to a high-voltage pulse. A bear pressing its wet nose against a wire completes the circuit and receives a painful (but harmless) shock, which conditions it to avoid the hive yard.
P(deter) = 1 − exp(−(V·nWires)/(k·barrierGap))
shock felt only if fence ON and bear reaches a wire
- Fence voltage — higher energizer output increases shock intensity and deterrence probability.
- Fence height (wire count) — more wires (closer spacing top-to-bottom) block a bear from reaching over or under.
- Bait/hive distance — how far hives sit from the fence line; closer placement tempts bears to push harder.
- Fence ON/OFF — toggling off simulates a power outage or disconnected fence — watch the bear walk right through.
- Send Bear In — triggers a new approach attempt so you can build up statistics.
Real application: USDA Wildlife Services data shows a well-maintained 3-5 wire electric fence at 6000+ volts deters over 90% of bear approaches to apiaries.