1. Kushiro Field Station, Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Kushiro, Hokkaido 085-0802, Japan
2. Central Fisheries Research Institute, Hokkaido Research Organization, Yoichi, Hokkaido 046-8555, Japan
3. Kushiro Fisheries Research Institute, Hokkaido Research Organization, Kushiro, Hokkaido 085-0027, Japan
4. Sapporo Field Station, Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Sapporo, Hokkaido 062-0922, Japan