Marine life in the upper layers of the sea may be endangered by increased ultraviolet (UV/ radiation resulting from reduction in the thickness of the earth’s ozone layer. There is undisputed observational evidence that human activities, including the production of chlorofluorocarbons, are influencing the concentration of stratospheric ozone (Watson, 1988). A significant reduction in average global stratospheric ozone is predicted over the next century, despite international efforts to address the problem. Seasonal depletions of ozone in the Antarctic during austral spring have already reached 50c/c, resulting in the widely discussed “‘ozone hole’” (Brasseur, 1987). Reduced stratospheric ozone will result in increased biologically damaging ultraviolet radiation (UV-B, 280-320nm) reaching the surface of the earth. Since UV-B radiation can penetrate to ecologically significant depths in water (Jerlov, 1950: Lenoble, 1956: Smith and Baker, 1979: Gieskes et al., 1989), any, ozone reduction results in increased UV-B penetrating the surface layers of marine environments.