2022 Volume 14 Issue 1 Pages 73-80
In this study, we investigated the effect of energized and non-energized 5-polywires electric fences (heights of 5-polywires: 20, 40, 70, 100, and 140cm) in preventing invasion by captive sika deer (C. n. nippon). Two experiments were conducted in an identical enclosure (400×600cm). In the first experiment, two 2-year-old captive sika deer (one male, one female) exposed to energized electric fences exhibited exploratory behavior toward the wires with their lips. Once the animals received an electric shock, they responded by either passing through the wires or stepping back from them. After receiving electric shocks by touching the wires a few times, the animals began to avoid the fences. The invasion-prevention percentage for both the female and male deer was 100% on day 4 after exposure to energized electric fences. In the second experiment, when the animals previously exposed to energized fences were exposed to non-energized fences, the female and male deer avoided the fences in the beginning but exhibited exploratory behavior toward the wires by touching with their lips on days 4 and 19 after exposure, respectively. Thereafter, female and male deer finally passed through the wires on days 7 and 43, respectively. Passing through was only observed between the wires placed at heights 40 and 70cm. The invasion-prevention percentage for both deer decreased gradually and was less than 20% at the end of the experiment. In conclusion, energized electric fences were highly effective in preventing invasion by sika deer. However, it was shown that sika deer passed through non-energized electric fences within a week of exposure even though they had previously received an electric shock from energized electric fences and learnt to avoid them. These results indicate the importance of daily maintenance of electric fences to keep them energizing.
