A study in the Caribbean has found that coral reefs can recover from global warming impacts, such as coral bleaching, if protected from fishing. Marine biologists have long been worried that coral reefs affected by climate change may be beyond recovery, however the new study published in PLoS ONE shows that alleviating another threat, overfishing, may allow coral reefs to cope with climate change.
Surveying ten sites of coral reefs in the Bahamas for two-and-a-half years the researchers found that even reefs severely damaged by coral bleaching could recover. In marine protected areas—where fishing is not allowed—coral cover increased an average of 19 percent. Coral reef cover outside of marine protected areas however showed no recovery.
“Our research shows that local action to reduce the effects of fishing can contribute meaningfully to the fate of reefs. The reserve allowed the number of parrotfishes to increase and because parrotfish eat seaweeds, the corals could grow freely without being swamped by weeds. As a result, reefs inside the park were showing recovery whereas those with more seaweed were not. This sort of evidence may help persuade governments to reduce the fishing of key herbivores like parrotfishes and help reefs cope with the inevitable threats posed by climate change,” explained Dr. Peter Mumby of the University of Exeter in a press release.
Coral bleaching, whereby corals face high mortality due to loss of vital symbiotic organisms, can be caused by a number of stresses, including higher water temperatures linked to global warming and ocean acidification, which is caused by higher CO2 levels in the ocean.
Despite the evidence of recovery, Mumby maintains that “in order to protect reefs in the long-term we need radical action to reduce CO2 emissions.”
Currently only 2 percent of the world’s coral reefs are in marine protected areas.
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