Growth and Survival of the Ark Shell Scapharca kagoshimensis Cultured in a Semi-enclosed Lagoon, Lake Nakaumi, Southwest Japan

Abstract

Growth and survival of the ark shell Scapharca kagoshimensis cultured within net-bags were examined under various environmental conditions in Lake Nakaumi. In summer, ark shells cultured in the surface layer of water showed higher growth than those in the bottom layer of water. In winter, ark shells cultured in the bottom layer showed higher growth than those in the surface layer. The growth and survival of ark shells were mainly influenced by dissolved oxygen in summer, while in winter, their growth was influenced by water temperature. These results indicate that hanging culture of the ark shells is possible using net-bags without bottom sediment, and also suggest that management of culturing depth is efficient for their growth through the year.