Relationship between plant communities in abandoned field and field sign of wild boar Sus scrofa Linnaeus in southwestern Tochigi Prefecture, central Japan

Abstract

Distribution of wild boars, Sus scrofa Linnaeus, has drastically expanded in the last decade, and agricultural damages ensuing this expansion has been a serious problem in rural areas with mixed forest and fields, which represents Japan's cultural landscapes (Satoyama). Because agricultural activity in these areas has an important role in maintaining high biodiversity, solving the human-wildlife conflict in Satoyama areas remains a practical issue for the farmers and wildlife managers, but is also important for the ecosystem management of these culturally valuable landscapes. We carried out this study at southwestern part of Tochigi Prefecture, central Japan. Total of 86 releves were sampled in abandoned fields of the study area. We classified plant communities in the abandoned fields, and created 1/2500 land cover map reflecting the classification of plant communities. To investigate relationships between the distribution of wild boars and habitat types, we surveyed field sign of wild boars in November, February, May and August of 2010-2011. Six types of plant community were classified as follows: Digitaria ciliaris-Eleusine indica community (C1a), Setaria faberi-Erigeron philadelphicus community (C1b), Echinochloa crus-galli-Arthraxon hispidus community (C2), Artemisia indica var. maximowiczii-Potentilla hebiichigo community (C3a), Miscanthus sinensis-Solidago altissima community (C3b) and Pleioblastus chino community (C4). The feeding sign of wild boars tend to be found in the community types, C3a, C3b, and C4, throughout a year. In November and February, the feeding sign also tended to occur in the community types, C1a, C1b, garden and orchard. In May and August, it tended to occur in bamboo groves, and riverside. The resting sign tended to be found in the community types, C3b and C4, in August. Among the plant communities in abandoned fields, the management of the community types, C3b and C4, were important to reduce agricultural damages from wild boars in Satoyama landscapes.