EFFECTS OF BODY SIZE AND WATER TEMPERATURE ON GRAZING RATES OF 4 INTERTIDAL GASTROPODS

Rates of radular activity were measured. in four species of Australian gastropods. The species were Austrocochlea constricta, Bembicium nanu m, Cellana tramoserica, and Nerita atramentosa. Work was done in Botan y Bay at Cape Banks, NSW, Australia from September 1989 to June 1990. A hydrophone was used to record radular raspings of snails in situ. Av erages based on all observations showed Cellana had the fastest rate w ith 80 rasps/min, and was followed by Austrocochlea (71 rasps/min), Be mbicium (57), and Nerita (39). Faster rates were associated with warme r water temperature and smaller body sizes in all species except Bembi cium. The potential for these differences in radular activity affectin g competitive interactions is discussed.