With only about one-sixth of their original coral cover remaining, most Caribbean coral reefs may disappear in the next 20 years, primarily due to the loss of two main grazers in the region, according to the latest report, Status and Trends of Carib- bean Coral Reefs: 1970-2012. It’s published by the Global Coral Reef Monitoring Network, the Inter- national Union for Conservation of Nature and the United Nations Environment Programme.
The report—involving 90 experts and an analy- sis of 35,000-plus surveys at 90 locations since 1970—included studies of corals, seaweeds, grazing sea urchins and fish. Climate change has long been thought to be the main culprit by making oceans more acidic and causing coral bleaching. Now, the loss of parrotfish and sea urchins is seen as the main factor; their demise has broken the delicate balance of coral ecosystems, allowing the algae upon which they feed to smother the reefs.
Restoring positive populations, plus protection from overfishing and excessive coastal pollution, could help the reefs recover and make them more resilient to future climate change impacts.
