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The use of dried Artemia biomass meal as an exclusive feed for postlarval white shrimp (Litopenaeus vannamei) was compared with four commercial feeds and three crustacean meals in a series of trials. Postlarvae (PL1-PL6) were stocked at a density of 1.5-2.5/litres in 16 tanks (100 litres volume) and fed, ad libidum, five times a day, over 23-29 days. Feeding postlarval shrimp with dried Artemia biomass resulted in a significantly larger size than feeding with three of the commercial feeds, and the crustacean meals. There was no significant size difference observed in animals fed with Artemia biomass and the commercial 'Golden Pearls' feed for postlarvae, however the coefficient of variation among the size of the 'Golden Pearls' fed animals was significantly higher. The weight increase of animals fed with Artemia biomass was higher than in animals fed with all the tested feeds. The survival rate was not significantly different in animals fed with Artemia flakes from 'Salt Creek', 'Bio-Marine', 'Golden Pearls' and Artemia biomass, however the survival rate was significantly larger in animals fed with Artemia biomass than in animals fed with the crustacean meals and 'Artemac.' Results suggest that dried Artemia biomass is a well-suited feed for postlarval L. vannamei.

To determine the optimum temperature for growth of the endangered intertidal purple snail Plicopurpura pansa (Gould 1853) (Prosobranchia, Muricidae), 731 adult specimens were reared in the laboratory on squid for 86 days at temperatures ranging from 20 to 32 1C. The snails showed extremely slow growth, if at all. Males and females raised at 26 1C grew the fastest, an average of 0.85 and 0.43 mm respectively. No statistically signi¢cant di¡erences were observed at other temperatures or between males and females. The best temperature for growth for the intertidal purple snail appears to be in the range between 26 and 30 1C.