Corals just can't seem to get a break these days. Another study has found that Caribbean coral species are slowly but steadily dying off, with dramatic potential implications for the region's ecosystem stability and structure. Ten percent of the 62 reef-building corals, including the elkhorn and staghorn corals which were once some of the Caribbean's most numerous species, are now under grave threat and likely to be listed as Critically Endangered on the International Union for the Conservation of Nature and Natural Resources' (IUCN) Red List of Threatened Species within the coming year.
Michael L. Smith, the director of the Caribbean Biodiversity Initiative at Conservation International, said that, "One of the Atlantic Ocean's most beautiful marine habitats no longer exists in many places because of dramatic increases in coral diseases, mostly caused by climate change and warmer waters."As the first in a series of Global Marine Species Assessments (GMSA) of key marine primary-producers, a group of scientists analyzed data on Western Tropical Atlantic corals, seagrasses, mangroves and algae earlier this year. Suzanne Livingstone, the GMSA programs officer, expects the species studied during the workshop to be added onto the 2008 IUCN Red List after a final review.
"Coral reefs support some of the richest areas of biodiversity in the world. When the coral reefs disappear, so will many other species which rely on reefs for shelter, reproduction and foraging," she said.
Having undergone one of the longest periods of human development sine the colonization of the Americas, the Caribbean corals were particularly hard hit by anthropogenic disturbances such as increased sedimentation in run-off water, over-fishing and coastal pollution. In addition, the combined effect of several natural disturbances including disease, hurricanes and bleaching, has further weakened the remaining stocks.
Although corals have certainly gotten the shorter end of the stick, mangroves have also been devastated by global warming and human development with some estimates placing mangrove cover loss in the region around 42% over the past 25 years. Forests are increasingly being cut down to accomodate further residential and aquaculture development throughout the region. Two out of the eight species are now listed as "Vulnerable to Extinction" while two others are in "Near Threatened" status.
Aaron Ellison, a professor at Harvard University, explained that "Mangroves protect shorelines, shelter fish, and filter pollution. The Caribbean was blessed with an abundance of these useful plants, but the consensus of this workshop is that mangroves are in trouble everywhere and need to be protected and restored."
Citing the examples of several healthy coral reefs living in marine protected areas (MPAs) scattered around the area, such as the Bonaire Marine Park in the Netherlands Antilles, the scientists urged immediate action to protect these remaining vestiges of Caribbean natural beauty. "Concentrated marine conservation and a global effort to halt man-induced climate change are necessary to preserve this vital economic engine in the region," said Kent Carpenter, GMSA director.