1. Aqua Restoration Research Center, Public Works Research Institute, Kawashima Kasada-machi, Kakamigahara, Gifu 501-6021, Japan
2. Laboratory of Aquatic Food Web Dynamics, Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Ehime, Japan
3. Faculty of Engineering, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan