Coral Disease Update

From Tropic Bird, a newsletter about inventory and monitoring activities, published by Friends of the Virgin Islands National Park

In July 1997, BRD (Biological Resources Division, U.S. Geologice Survey) scientists began documenting what appeared to be new coral diseases around St. John using underwater video and still photography. Some of these diseases resemble ones seen off of Florida and other Caribbean islands. Colonies of the dominant coral around St. John have patches without any tissue. These bright white areas of exposed skeleton are rapidly colonized by algae. This disease is even showing up on reefs which are relatively undisturbed by humans. Samples of diseased coral tissue have been sent to microbiologists for examination. In addition, one pathogen, a rare terrestrial fungus which causes disease in sea fans, was isolated from an air sample taken on St. John during an African dust event. Further analysis of data from reef fish monitoring has provided even more evidence of alarming declines and shifts in relative abudances of these fishes. The St. John trap fishery is exhibiting several patterns associated with overfishing, including fewer fish and smaller fish in traps, more herbivorous fishes and fewer groupers in traps. Based on the information from this and several other projects, Virgin Islands National Park is seriously considering designation of a marine reserve within Park Waters.

Note: BRD's Jeff Miller, a marine biologist talks weekly on "The Living Reef" at Maho Bay Camps. See the weekly What's Happening at Maho for information on day and time.