Epibenthic predation in marine soft-bottoms: Being small and how to get away with it

Abstract

In intertidal soft-bottoms, epibenthic predation is one of the most important post-recruitment processes. Small juveniles are particularly susceptible to predation, and they often settle in the high intertidal where predation pressure is relatively low. Growth conditions in the high intertidal are, however, only suboptimal compared to the low intertidal. Juvenile amphipods Leptocheirus pinguis usually remain in their mother's burrow for extended time periods growing to average sizes of 4-6 mm during this extended parental care. In laboratory experiments, more juvenile amphipods survived in controls than in predator additions. In the predator treatments, most adult amphipods survived while many juveniles disappeared. Medium-sized juveniles (6-10 mm size) that had already established their own burrows emigrated in large numbers from the predator treatments whereas most of the adult females remained as residents in these trays. Juvenile L. pinguis survived periods where they are most susceptible to epibenthic predation in the protected burrows of their mother. Extended parental care enables juvenile amphipods to recruit immediately into the adult habitat with a good survival chance. It is hypothesized that some small soft-bottom infauna find protection in the burrows of other infauna, medium-sized infauna is most likely to engage in escape reactions, whereas large infauna build their own, deep, burrows, safe from epibenthic predators. ©1997 Kluwer Academic Publishers.