Experimental Studies on the Predation of Juvenile Sea Cucumber, Stichopus japonicus by Sea Star, Asterina pectinifera

Abstract

This study investigated the effect of prey size and water temperature on the predation of juvenile sea cucumber, Stichopus japonicus, by sea star, Asterina pectinifera. Sea stars (average arm length 43.3 mm) ate an average of 1.8, 0.5, 0.1, and 0 sea cucumbers/day/predator when the average body lengths of the prey were respectively 15.9, 30.1, 40.0, and 54.6 mm. Likewise, sea stars (average arm length 46.2 mm) ate 0.9, 0.8, and 0.2 prey (average body length 29.2 mm) / day/predator when held at temperatures of 20, 15, and 10°C. It is concluded that the predation rate of sea cucumber by sea star decreases with increased prey size or lower water temperature.