Effects of environmental factors on larval settlement of sea cucumber, Apostichopus japonicus (Selenka)

Abstract

In this study, a series of experiments were conducted to evaluate the influence of environmental factors on larval settlement of sea cucumber, Apostichopus japonicus (Selenka). These experiments examined the following factors: temperature (18, 21, 24, and 27 C), salinity (20, 25, 30, and 35 ppt), and diet supply (micro-algae, macro-algae, sea mud, and a mixture of macro-algae and sea mud). Results indicated that larval settlements were significantly different among different temperatures, salinities, and diet supplies (P < 0.001). Lower temperature between 18 and 21 C and a salinity of 30 ppt were the optimum for larval settlement of A. japonicus. The sediments (macro-algae and sea mud) replaced micro-algae as a food source for the newly settled juveniles with an increase in metamorphosis and early settlement. © by the World Aquaculture Society 2010.