Ungulates-exclusion grates as an adjoining facility to crop damage prevention fences

Abstract

In many cases, fences are effective against human-wildlife conflict if the fences are properly constructed and maintained. However, wildlife is able to intrude fences where they intersect with roads. The purpose of this study was to evaluate techniques and strategies for improving the effectiveness of barrier fences in these vulnerable areas. This study developed the grates which are directly laid on the road. The grates used slanted steel panels which induce slippage of ungulate hooves down into the grates; therefore, ungulates cannot normally walk on the grates. To survey the best design of the grates, small-scale experiments were conducted in the forest. Seven types of grates were tested in four sites and the experiment showed that the most effective grates had 35° slanted panels and the distance between panels was 100 mm. Using the most effective grates, this study conducted an actual road test and the grates effectively reduced the deer passing the road (98.5% reduction). The advantages of our grates are (i) costs of digging and constructing a sub-footing using heavy machine is zero, (ii) < half-length of old type grates. Shorter grates (2.4 m) without sub-footings are safer for vehicles and walking children.