| Popis: |
The effects of increasing voltage and the use of different conducting materials (steel-wire and polywire) on the efficacy of an electric fence to exclude badgers ( Meles meles ) were assessed in a field trial conducted in the south-west of England. Fences were erected to prevent badgers feeding at bait points to which they had previously had unrestricted access. The effectiveness of both steel-wire and polywire fences maintained at 6 kV was compared with that of fences in which the voltage was increased, in 2 kV steps, from 0 to 6 kV. Effectiveness was measured by comparing bait consumption before and after fence erection. Behavioural observations were conducted to determine how badgers reacted to the different fence types. Both the steel-wire and polywire fences, maintained at 6 kV throughout, proved effective at excluding badgers (steel-wire 90%; polywire 89%). Unelectrified fences (0 kV) afforded virtually no protection at all. As the voltage was stepped up there was a corresponding increase in the level of effectiveness. At every voltage stage, the steel-wire fence appeared to be more effective than its polywire counterpart (0 kV: steel-wire 4%, polywire 3%; 2 kV: steel-wire 68%, polywire 34%; 4 kV: steel-wire 83%, polywire 56%; 6 kV: steel-wire 95%, polywire 63%). The proportion of badgers observed to cross the staged-voltage fences fell with increasing voltage. A smaller proportion was observed to cross the steel-wire design. Most badgers crossed by means of pushing between the upper wires. The results suggest that landowners and occupiers considering the use of electric fencing to exclude badgers should, whenever possible, use steel-wire in preference to polywire. Fence voltages should not be allowed to fall below 4 kV, particularly during the first few weeks after erection, if effective management is to be achieved. |
Full Text from ScienceDirect