First Author:   Hiroki Wakamatsu Fisheries Research and Education Agency hwakamatsu@affrc.go.jp   2-12-4 Fukuura, Kanazawa-ku, Yokohama,, 236-8648, 日本   +81-80-6185-6547(Phone) +81-80-6185-6547(Fax) Second Author: Seiichi Fukui Osaka Sangyo University seifukui@eco.osaka-sandai.ac.jp   Osaka, 574-8530, Japan       Third Author: Kana Miwa Kushiro Public University of Economics miwa@kushiro-pu.ac.jp