Recognizability of algae ingested by abalone

Abstract

Studies of the diet of abalone and other herbivorous gastropods, based on gut contents, may be biased against some species of algae, especially those that are most preferred. The blacklip abalone Haliotis rubra was fed for short periods on monospecific diets of eight algae, including red, brown and green species that span the range of preference. In addition, two preferred species were fed to abalone after one month’s, one week’s, or no starvation. The number of recognizable fragments of each alga per unit volume of crop contents was examined. Although key characters of some species remained recognizable even at an advanced stage of digestion, other algae were intrinsically less recognizable..