Feeding behavior and growth of Hermissenda crassicornis (Mollusca: Nudibranchia) in the laboratory

The feeding behavior and growth of the nudibranch mollusc Hermissenda crassicornis, a generalist carnivore, has been studied; this species is widely used as a biomedical and neurobiological model. Relative to the stalks, polyps of the hydroid prey, Tubularia crocea, were preferentially consumed by adults of H. crassicornis at a fast rate. Starved slugs did not distinguish between reproductive and unreproductive polyps, but unstarved slugs did select unreproductive polyps of T. crocea. Experiments with diets based on different parts of T. crocea (polyps, stalks, or whole) showed no obvious differences in juvenile growth among treatments, but survival of juveniles was low. Juveniles of H. crassicornis grew better on a diet of the small anemone Haliplanella luciae than on T. crocea or the anemone Metridium senile. The relationship between body length and wet weight of H. crassicornis was similar for animals grown in the laboratory on a T. crocea diet and specimens from the field.