Enteromorpha flexuosa is a filamentous light green alga with worldwide distribution in shallow brackish or marine habitats (Mairh, Pandey and Tewari 1986, Littler and Littler 1989). The term 'enteromorpha' literally means 'intestine shaped' and is used to describe the hollow, tube-like filaments of this species.E. flexuosa grows to 20 cm but generally tends to be smaller. It typically grows in clusters on mangrove roots, rocks, wood or as an epiphyte on other plants. It is found at depths ranging from the high intertidal zone to approximately 5 m. below the surface. Species of this weedy genus are often the first to colonize open substrata (Beach et al. 1995). The ecological success of E. flexuosa and other pioneering species is in part attributed to the readily available pool of motile unicells that are able to rapidly colonize new areas. The chance for successful settlement of these cells is greatly enhanced because gametes and zoospores of this species remain viable for 10 or more days due to their ability to photosynthesize, often achieving photosynthetic rates approaching those of the adult thalli (Beach et al. 1989).