Rates of feeding by Thais (Nucella) Lapillus (L.)

Abstract

A hyperbolic relation between size of Thais lapillus (L.) and preferred prey ( Mytilus edulis L.) size has been found. Times spent drilling and ingesting the prey did not vary for snails of different sizes, but were shorter at higher temperatures. There was an allometric relation between prey size and the duration of a post-feeding phase; this relationship also was sensitive to temperature. Feeding was more intense in the summer than winter, and this was not due solely to the higher temperatures in the summer. During the winter enforced starvation did not result in greatly increased feeding activity, but in the summer the longer the period of starvation the more intense was the feeding behaviour. Assimilation efficiency of Thais for Mytilus flesh was 66%. These results, together with values for oxygen consumption from a related study, were used to predict growth and net energy intake values for Thais of different sizes.