1. Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510, Japan
2. Wildlife Management Center, Tokyo University of Agriculture and Technology, 3-5-8, Saiwaicho, Fuchu, Tokyo 183-8509, Japan
3. Azabu University, 1-17-71, Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5201, Japan