While bacterial infections have been cited as causes of coral bleaching,it is difficult to attribute these agents as unequivocal causal factors. Infection of coral hosts in the laboratory has produced bleaching (Kushmaro et al. 1996), but only in small volume static systems wherehigh doses of bacteria were applied at temperatures which represent the upper range limits of the corals used. Further more the extra polation of these results to thefield, where examination of bleached corals revealed large aggregations of rod-shaped bacteria, does not necessarily imply cause and effect.