Malacological Society of Australasia

Molluscan Research

Volume 18, Issue 2 (Australasian Abalone): 31 October 1997. Edited by S.A. Shepherd, P.E.McShane and F.E.Wells

Feeding effects of postlarval red abalone, Haliotis rufescens (Mollusca: Gastropoda) on encrusting coralline algae.

Christopher L. Kitting* and Daniel E. Morse.

Department of Biological Sciences, and the Marine Science Institute, University of California, Santa Barbara, California 93106, USA.
*Present Address: Department of Biological Sciences, California State University, Hayward, California 94542, USA.

Detailed examinations of an algal -microherbivore symbiosis have revealed mutualistic components of such herbivore-plant interactions. High-resolution photomicroscopy and experimental analyses in the field laboratory were used to evaluate effects of foraging by Haliotis rufescens (red abalone) postlarvae ~ 200 µm in length, on their encrusting red algal hosts, Lithothamnion (=Lithothamnium) californicum, Lithophyllum lichenare, and Hildenbrandia rubra (= H. prototypus). We have quantified the microscopic food availability, postlarval foraging behaviour, changes in stomach and faecal contents, growth, and mutualistic effects of grazing. Host algae were found to benefit both from a reduction in coverage by epiphytic algae, and from enhancement of vegetative growth.

pp. 183-196.