Epiphytic luminous and non-luminous bacteria were determined quantitatively for eight intertidal algal species from rocky beaches of Goa and Lakshadweep coral reef lagoon. Luminous bacteria were present on all eight algal species and contributed 2-11% of the total viable epiphytic bacterial population. Vibrio harveyi (over 65%) was the dominant species, whilst V. fischeri made up a further 25% of the total. Photobacterium leiognathi comprised only 10% of the total, and contained none of the investigated enzymes. No luminous bacteria examined produced cellulases, but both V. harveyi and V. fischeri strains produced substantial amounts of alginate and pectin lyases. In contrast, cellulase activities were pronounced in non-luminous vibrio, pseudomonad and alteromonas bacteria. Vibrios, pseudomonads and the aeromonad bacteria also showed higher alginate lyase, but only moderate pectin lyase activities. From the results of this study, it appears that epiphytic bacteria utilise the algal nutrients selectively and are important in the biotransformation of marine algae