Coral Mortality and African Dust

Diadema Die-off

Sea urchin Diadema: Underwater photograph of the urchin Diadema on a coral head taken before 1983. In the summer of 1983 most of these urchins died throughout the Caribbean. Notice how the Diadema have kept the surface of this dead coral free of algae. Today, without the browsing of these algae-eating urchins, dead coral surfaces such as this are coated with mats of fleshy alga [see Algal Infestation]. Such growth of fleshy alga retard the establishment of coral larvae. large version [136 k]