Fecundity of snow crab Chionoecetes opilio off Wakasa Bay in the Sea of Japan

Abstract

916  0422 , 2 Fukui Prefectural Fisheries Experimental Station, Tsuruga, Fukui 914  0843, Japan To determine fecundity, female snow crabs Chionoecetes opilio were caught oŠ Wakasa Bay. The number of oocytes for pubescent females ( prior to the terminal molt; mean carapace width 66.2 mm previously reported oŠ Wakasa Bay ) and for young adults ( spawners less than 4 years after the terminal molt; 77.4 mm ) correlated with the carapace width. However, the number of oocytes for pubescent females was 62.8  that of young adults. The diŠerence in the number of oocytes might be caused by the body size when they developed their ovaries. Because the number of eggs attached to pleopods for primiparae ( primary spawners ) and young multiparae ( repeat spawners within 1.5 to ＜ 4 years after the terminal molt ) originated during the ovarian development of pubescent females and young adults, respectively, the number of eggs for primiparae was 66.3  that of young multiparae. The number of oocytes eggs aged than 4 years after the those for young multiparae there was no correlation with their width, probably