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| Earth on Sep 15, 2012

Large coral loss seen over some Caribbean reefs

The International Union for Conservation of Nature reports that live coral cover has dropped to less than 10% over some Caribbean reefs.

On September 7, 2012 the International Union for Conservation of Nature (IUCN) released a report that tracks the deterioration of coral reefs in the Caribbean over the past 39 years. The report indicates that live coral cover over some reefs in Jamaica, Puerto Rico, the Florida Keys and the US Virgin Islands has dropped to less than 10%. These losses are thought to be driven by a combination of factors including hurricanes, disease, overfishing, pollution and climate change.

In early May 2012, 36 scientists from 18 different countries gathered at the Smithsonian’s Tropical Research Institute in the Republic of Panama to begin the enormous task of assessing coral reef conditions around the world as part of a program called the Global Coral Reef Monitoring Network. The program, administered by the IUCN, is planning to release a global synthesis report of their findings in 2016.

Corals in Belize. Image Credit: Jean-Marc Kuffer via Flickr.

On September 7, 2012 the IUCN released a preliminary report describing the conditions of coral reefs in seven different countries located in the Caribbean.

The new report (pdf) found that total live coral cover from all of the countries examined declined from a high of approximately 58% in 1973 to a low of approximately 8% in 2012.

Among the countries, coral reefs in Bonaire, Curacao and the Cayman Islands showed the least amount of loss, and live coral cover currently ranges from about 20 to 28% in these areas. Reefs in Jamaica, Puerto Rico, the Florida Keys and the US Virgin Islands were found to be the worst off with live coral cover currently ranging from as little as 8 to 10%.

Elkhorn coral with white band disease. Image Credit: Andy Bruckner, NOAA.

Species of Staghorn and Elkhorn corals in Caribbean have been particularly hard hit by white band disease, the report notes. White band disease is a disease in corals whereby live coral tissue dies off leaving behind a discolored band that consists of the corals’ white calcium carbonate skeleton.

Jeremy Jackson, Science Director of the Global Coral Reef Monitoring Network, and his co-authors of the report commented that:

Caribbean reefs with the highest surviving coral cover and least macroalgae tend to be characterized by little land-based pollution, some degree of fisheries regulations and enforcement, moderate economic prosperity, and lower frequency of hurricanes, coral bleaching, and disease. Unraveling the potential interactive role of these and other factors is a major goal of our study once all the necessary data are available.

The full synthesis report containing information about coral reef conditions throughout the Caribbean is expected to be published and available online by March 2013.

Clearly, the amount of live coral cover on Earth will be an important metric to consider in the years ahead.

Bottom line: On September 7, 2012 the International Union for Conservation of Nature (IUCN) released a preliminary report that found that live coral cover over some reefs in Jamaica, Puerto Rico, the Florida Keys and the US Virgin Islands has dropped to less than 10%. The losses are thought to be driven by a combination of factors including hurricanes, disease, overfishing, pollution and climate change. A full synthesis report containing information about coral reef conditions throughout the Caribbean is expected to be published and available online by March 2013.

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