Rooting sites of wild boar in Shingo and Himuro Districts of Sano, Tochigi Prefecture

Abstract

To determine the foraging sites of wild boar (Sus scrofa), we conducted a rooting-track census between 2010 and 2011 in hilly (Shingo District) and mountainous regions (Himuro District) of Sano, Tochigi Prefecture. We also collected and analyzed boar feces during the study period. The number of rooting tracks was found to be significantly higher in abandoned fields than in other land-cover types in autumn and winter in Shingo and throughout the study period in Himuro. In addition, fibers (including undigested residues of roots, stems, and leaves) and monocots were frequently found in feces sampled throughout the period in both areas. These findings indicated that wild boar foraged at abandoned fields, where graminoid plants were predominant. In both regions, the number of rooting tracks was higher in bamboo forests in spring and summer, and shoots of bamboo were frequently found in feces sampled in spring. This may be associated with seasonal changes in food availability (i.e., growth of bamboo shoots). The number of rooting tracks was lower in coniferous forests in both regions and in human settlements in Shingo. The results of the present study indicated that the selection of foraging sites by wild boar was mainly associated with food availability and sometimes affected by the intensity of human activities.