ST. CROIX, Virgin Islands (23 August 2006) -- Scientists with the National Oceanic and Atmospheric Administration's Coral Reef Watch have issued a warning to scuba-dive operators and fishery managers to be on the lookout for signs of coral bleaching after satellite images taken earlier this week reflected above normal temperatures in the Caribbean Sea. Al Strong, a scientist with NOAA's Coral Reef Watch, said the sea surface temperatures around Puerto Rico and the Virgin Islands reached 83.66 degrees Fahrenheit on Tuesday - surpassing highs not normally expected until September and October. "We've been seeing temperatures above normal all of this year," Strong said on Wednesday. "There is a concern that with the temperatures already above normal, it would continue to warm." Strong stopped short of saying the above-normal temperatures signaled a repeat of last year's devastating coral-bleaching event that killed 40 percent of coral reefs in the territory. However, he said scientists will continue to monitor the sea temperatures for the next 30 days. If water temperatures keep going up, scientists fear the coral reefs may suffer more damage. NOAA is alerting scuba-dive operators and underwater researchers in the territory to look for coral damage and to be careful around the reefs, which are easily damaged by physical contact. U.S. Geological Survey Research biologist Erinn Muller, who works with the National Park Service on St. John, said the satellite imagery is important because it keeps researchers on their toes. While NOAA satellites are looking at surface temperatures, Muller said her agency and the Park Service are measuring temperatures beneath the surface at monitoring sites around St. John and St. Croix. "The temperature gauges in the water will give you a much more accurate and reliable reading in real time," Muller said. She said when readings of the underwater gauges were last taken at the end of July, temperatures in Virgin Islands waters had reached 84 degrees. "We know the waters are warm and they typically get warmer during the summer months," Muller said. "We can't predict right now if we will see a repeat of last year." Last year, eight key reefs in St. John and St. Croix that are monitored by the Park Service showed signs of deterioration as a result of overheated waters. Biologists became cautiously optimistic when heavy rains in October caused ocean temperatures in the region to drop and they observed the first stages of recovery from the bleaching event. | | In 2005, coral bleaching devastated coral reefs in the Virgin Islands. But weeks after the corals recolored, patches of death tissue began appearing. Officials said a disease, possibly unique to the region, destroyed nearly 40 percent of the coral at the Park Service's monitoring sites in just 10 months. Muller said biologists will keep close watch on the coral reefs and sea temperatures in the coming weeks. She said recent overcast skies, periods of heavy rains and windy conditions have kept the high temperatures below the surface down and they hope those conditions continue. Muller said that while coral species acclimate to warmer temperatures, a half a degree can make a whole lot of difference. High sea temperatures stress coral, making the fragile undersea life more susceptible to disease and premature death. A building block for undersea life, the coral reefs are a sheltered habitat for fish, lobsters and other animals to feed and breed. SOURCE - Virgin Islands Daily News |
