Date of Award

Spring 5-15-2011

Document Type


Degree Name

Bachelor of Science (BS)




College of Science

First Advisor

Erin J. Burge


The long-spined sea urchin, Diadema antillarum, is a well-studied keystone herbivore on Caribbean coral reefs. The sea urchin controls benthic algae populations by grazing on macroalgae. Destruction caused by Hurricane Allen in 1980, along with the mass mortality of this urchin in 1983, greatly impacted Caribbean reef systems. In Discovery Bay, Jamaica, Diadema densities have been heavily studied over the years, allowing a review of their recovery and a prediction of their future. In Discovery Bay, densities were recorded to be up to 9.3 and 13.9 ± 2.8 m-2 at 5 m depth on the forereef before the mass mortality. After this event, values were found to be zero, or nearly zero, at multiple depths up until the mid 19902. Diadema have shown a recovery in numbers as densities in the late 2000s ranged between 3.94 ± 0.68 and 4.39 ± 0.4 m-2 at 4 – 6 m depth. In most of the wider Caribbean, recovery has been absent with values in many locations still nearly zero, with the exception of St. Croix and Dominica. We predict that Diadema densities will continue to increase in the future, but the rate will be slower than that recorded over the past 27 years.

Included in

Biology Commons