A PHYSIOLOGICAL APPROACH TO MARICULTURE OF RED ALGAE

Algal mariculture research at Hopkins Marine Station (Stanford University) and Marine Bioassay Laboratories (Watsonville, Calif.) led to the development of a critical pathway approach: ecological studies, strain selection, physiological experimentation, and cultivation trials. Initial ecological studies focused on seasonal growth and life history patterns of Gelidium and Gracilaria . The results provided the clues for selection of experimental tolerance ranges for key physical and chemical parameters to be studies. Plant vigor and the algal products of interest were the primary criteria in the strain selection program. The metabolic response patterns for net photosynthesis of the species were then studied to characterize the presumptive environmental optima and tolerance ranges for these red algal cultures. The results from these shortterm physiological experiments are tested in algal cultivation trials. The results from this critical pathway approach were: 1) selected, vigorous strains; 2) basic requirements for cultivation of the species; 3) predictions of how the species will respond in culture; 4) production estimates for use in mariculture feasibility models; and 5) a definition of conditions which must be met by a specific culture technique. This research, which takes place primarily in the laboratory, provides the foundation for development of the capital‐intensive, pilot mariculture system for a specific red algal species.