1. Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan, and Laboratory of Aquatic Food Web Dynamics, Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, 790-8566, Ehime, Japan
2. Graduate School of Humanities and Sciences, Nara Women’s University, Kitanoya‐nishimachi Nara 630-8506, Japan, and Aqua Restoration Research Center, Public Works Research Institute, Kawashima Kasada-machi, Kakamigahara, Gifu, 501-6021, Japan