Global warming contributing to coral decline


American and Australian scientists have found evidence that global warming may be responsible for increasing incidences of coral disease.

Publishing their results in the latest issue of the journal PLoS Biology, John Bruno, Elizabeth Selig, Kenneth Casey, Cathie Page, Bette Willis, Catherine Harvell, Hugh Sweatman, and Amy Melendy compared survey data gathered over six years in the Great Barrier Reef with new ocean temperature data obtained via satellites to test for correlation between rising ocean temperatures and increasing outbreaks of white syndrome, a coral disease.

White syndrome is a disease whose root cause is unknown, causing corals to undergo premature programmed cell death.

The authors found that warm temperature anomalies were positively correlated with the frequency of white syndrome outbreaks on the Great Barrier Reef, but that this correlation was only observed at high coral density.

The authors also state that: "Our results are supported by basic epidemiological principles, and could apply to other coral disease systems and to disease ecology in general.

However, coral disease dynamics are likely to be affected by a variety of biotic and abiotic factors, the relative importance of which will vary among regions, scales, and species."

For more information, see the paper: Bruno JF, ER Selig, KS Casey, CA Page, BL Willis, CD Harvell, H Sweatman and AM Melendy (2007) Thermal stress and coral cover as drivers of coral disease outbreaks. PLoS Biology 5, e124, 1220"1227.