Caribbean corals decline 80% in 25 years

Coral reefs across the Caribbean have suffered a phenomenal 80% decline in their coral cover during the past three decades, reveals new research from the University of East Anglia (UEA) and the Tyndall Centre for Climate Change Research, published this week in the international online journal Science Express.

The amount of reef covered by hard corals, the main builders of reef framework, has decreased on average from 50% to just 10% in the last 25 years. Although the majority of the loss occurred in the 1980s, there is no evidence that the rate of coral loss is slowing.

“The feeling among scientists and tourists has long been that Caribbean corals are doing badly, since many people have seen reefs degrade over the years. We are the first to pull information together from across the region and put a hard figure on coral decline. The end result has surprised us. The rate of decline we found exceeds by far the well-publicised rates of loss for tropical forests”, said Toby Gardner, the lead author who compiled the data, and Dr Isabelle Côté, a specialist in tropical marine ecology in UEA’s School of Biological Sciences.

The causes of coral decline are thought to include natural factors, such as hurricanes and disease, and man-made ones, like over-fishing, pollution, and sedimentation caused by deforestation, which smothers the coral. The consequences of disappearing coral can be far-reaching, from the collapse of reef-associated fisheries, to dwindling tourism, to increased coastal damage sustained during hurricanes.

“The good news is that there are some areas in the Caribbean that appear to be recovering. The bad news, however, is that the new coral communities seem to be different from the old ones. We don’t know how well these new ones will be able to face the challenges of rising sea levels and temperatures, that result from global warming”, warns Dr Côté.

“Caribbean reefs host extraordinary biodiversity, provide a livelihood to millions of people, and essential physical protection from tropical storms” said Professor Andrew Watkinson, leader of the Tyndall Centre’s research into climate change and the coastal zone. “Now that the extent of the plight of Caribbean corals has been measured, there is renewed urgency for conservation action to restore this unique and important ecosystem”.

The research paper, Long-term region-wide declines in Caribbean coral, was written by Toby Gardner, Isabelle Côté, Jennifer Gill, Alastair Grant and Andrew Watkinson.