Changing Planet

Caribbean Coral Reefs Mostly Dead, IUCN Says

The Caribbean’s coral reefs have collapsed, mostly due to overfishing and climate change, according to a new report released by the International Union for Conservation of Nature (IUCN).

In the most comprehensive study yet of Caribbean coral reefs, scientists have discovered that the 50 to 60 percent coral cover present in the 1970s has plummeted to less than 10 percent.

“I’m sad to tell you it’s a dire picture,” Carl Gustaf Lundin, director of IUCN’s Global Marine and Polar Programme, said at a news briefing Friday at the World Conservation Congress in Jeju Island, South Korea.

Called “Nature’s Olympics,” the conference will explore five environmental themes over five days. Today’s theme is Nature+ Climate, which focuses on how to combat global warming.

A Caribbean Sea reef off Belize. Photograph by Mazyar Jalayer, My Shot

Much of the decline is caused by a massive die-off of sea urchins in the 1970s—possibly due to disease. Without these reef grazers—the “cows in the field” that keep vegetation in check—the number of algae and grasses have skyrocketed, dominating reefs and pushing corals aside, Lundin said.

What’s more, overfishing of grazer species such as parrotfish or surgeonfish is allowing more algae to take over and outcompete the coral, said Ameer Abdulla, IUCN senior advisor on Marine Biodiversity and Conservation Science.

“Coral reef communities are just like human communities—there are different roles that are fundamental to keeping the system going,” Abdulla said.

For example, if all the engineers were taken out of a human society, that would affect how the society functions.

The same phenomenon is happening with the loss of the Caribbean’s grazers, he said.

Parrotfish are like the cows of the sea, keeping algae in check. Photograph by Chriskraska Kraska, My Shot

Global Warming Also at Play

The scientists also said that warmer water—often caused by hurricanes blowing through—have harmed reefs. When the water gets too hot, algae that live inside coral, called zooxanthellae—abandon their hosts, causing the coral themselves to bleach and eventually die.

Though some reefs can bounce back from such periods of warmer water, notably in the Indian Ocean, “We have heating happening with much higher frequency and for longer duration,” Lundin told National Geographic News.

For instance, some 500-to-a-thousand-year-old corals in the Indian Ocean have died due to warmer water.

“We know with some certainty we haven’t had this happen for a thousand years, that’s a clear indication that something’s afoot,” Lundin said.

“For those that are very skeptical of what’s happening with climate change, I would say reality is not in their favor.”

Caribbean Collapse a First—Others May Follow 

Corals are vital for many reasons, from boosting tourism dollars to local communities and even buffeting islands themselves from powerful storm surges, Lundin said.

The good news is that there are ways to protect the remaining 10 percent of Caribbean corals.

“The urgency of improving management is certainly there—our message is we need to encourage the people who are the custodians of the resources to take charge. We do know a lot about what one can do,” said Lundin.

For instance, putting in place marine protected areas can reduce the pressure of overfishing. Governments can also work with local fishers to maintain their livelihoods, for instance by raising the value of individual fish so that the fishers catch fewer animals.

The bottom line, Abdulla said, is that “the Caribbean system is one of first systems to experience collapse—it’s something that will happen across the globe if human use of coral reefs continues as it is.”

Christine Dell’Amore, environment writer-editor for National Geographic News, is reporting from the IUCN World Conservation Congress in Jeju Island, South Korea.

Christine Dell'Amore, environment writer/editor for National Geographic News, has reported from six continents, including Antarctica. She has also written for Smithsonian magazine and the Washington Post. Christine holds a masters degree in journalism with a specialty in environmental reporting from the University of Colorado at Boulder. Her book, South Pole, was published in 2012.
  • Craig Quirolo

    Seeing is believing….. go to to see and download for free images from coral reefs in the Caribbean and the Florida Keys focusing on coral disease. Coral is well on its’ way down the proverbial slippery slope

  • Mermaiden

    WE live to snorkel and dive. It is a sacred, joyful, soul-stirring activity. So much fun, you feel the joys of childhood, and at the same time, a profound peace. WHY, WHY, WHY, is there not a much more proactive effort to SAVE ALL OF THEM, EVERYWHERE? That’s how all the islands make their money. COME ON NOW, BEFORE IT’S TOTALLY TOO LATE. …………

  • mandy

    while everything the article says is true, the “solutions” presented as hopeful are so far short of what is needed, and so simplistic as to be discouraging to conservationists, divers and local fishermen… none of the recommended measures helps with the warming of the waters, even when enforceable… are there no new ideas?

  • eric

    The industrial civilisation (that also allows coral studies amongst other things) will most probably collapse soon anyway, the fact that we are currently at the global oil production peak (maximum of flow) being the main driver for that.

  • eric

    and any American pretending to care about coral or the climate, would first ask for major volume based taxes to be put on fossile fuels

  • Arun Madisetti

    What sites or locations were used to base this awfully broad statement

  • Ken

    Records taken from ice cores and tree rings show the Earth has been in a cooling trend for at least 2000 years, until the recent 30-50 years. The Earth was warmer in the middle ages and even warmer during the Roman Empire days than it is today.
    What did the corals do during those warmer times?

  • Christine Dell’Amore

    Hi Arun, if you scroll down to the bottom of this webpage, you will see a PDF of the report, which provides the information you’re looking for on sites and locations studied. Cheers, Christine

  • mark

    Sorry that the report did not focus more strongly on overfishing as the problem. Temperature isn’t killing the coral; over the last few million years coral can and has handled strong termperature variations. Overfishing by contrast, is something that is directly caused and maintained by human activity. Further, there’s lots of successful regulatory models on how to stop overfishing.

  • Josh


    Coral is resilient, and can survive at warmer (or colder) temperature levels. However, when ocean temperatures shift drastically over a short time span, coral bleaching (often followed by death) is inevitable.

    “How fast the oceans warm will largely determine whether coral survive … Coral can adapt to a changing climate. Some coral species have been around for thousands of years and adapted to many changes in climate since then. However, coral may not be able to adapt fast enough to the present rate of climate change.”

  • Bob

    News to me. While everyone knows coral is under pressure, “mostly dead” is probably an excessively exuberant choice of words. I went diving a year ago off Costa Verde in Cuba, and the reefs there, once you get far enough out, are healthy and beautiful.

  • Steve

    That’s not even a healthy reef in the picture that they label as such. Those are dead coral heads covered in coralline alge and encrusting sponges with a few gorgonians. This is typical of an impacted reef. If one considers this to be a healthy reef, then they sadly haven’t had experience with a healthy Caribbean reef to use as a comparison.

  • Ed Hughes

    Scuba my Seattle dives.
    Sea urchane produce millions of young. They are the rats of the ocean. In 1 year you could with 2 or 3 sea urchans produce millions and millions of sea urchans. For get the parrot fish it has little or no impact compared to a feild of a million sea urcaqns.
    What is problem with one breading you could seed a million a week.

  • Brad

    The coral around Cuba is in beautiful, pristine condition because after the Soviet Union broke and they stopped supplying the island with large amounts or fertilizers the farmers were forced into more green farming practices. As a result, all those chemicals are gone and corals like Stag Coral have made a huge comeback, not seen in the more industrialized areas of the Caribbean like the United States.

  • eric

    By the way, did you people know that the carribeans were full of seals when Europeans arrived ?
    (similar species as current monk seals in Hawai and remaining few mediterraneans ones) :

  • Christine Dell’Amore

    @Bob—Cuba is actually one of the regions that’s still relatively healthy, according to the report that I linked to below. Ten percent of Caribbean reefs are still intact.

    @Steve—apologies, that was my fault. I assumed the picture I found in our My Shot database depicted a healthy reef. I’ll take out the word “healthy.”

    Thanks to everyone for their comments!

  • theron lyda

    Craig Quirolo and Deevon, his wife have devoted their lifes to saving the coral…Their… non-profit Reef Relief in Key West is the org. to support, if saving the reef is important. Many changes,as to how the reef is treated by industrial tourism, removing phosphates from laundry soap, photo-monitoring, of the reef, over years of time, of Cuba and the Carribean, can be credited to Reef Relief….Planting coral has been a project supported in the Keys… Please Donate time or more to this worthy Organizatation…..

  • Claire A. Nelson

    The truth is that the average Caribbean Citizen does not know much about the Sea and the fragile ecology of the Sea, The Sea is just there… like air and it is taken for granted. That is why we at the Instittute of Caribbean Studies have launched CARIBBEAN SEA FUTURES INITIATIVE. The multi-pronged initiative is aimed at developing awareness and research and education and policy aimed at ensuring the sustainable utilization of the Caribbean Sea. The Conference is slated to take place in 2013. Meanwhile Research Centers in Universities interested in creating Academic Partnerships are invited to attend the Academic Exchange Forum slated for December in JAMAICA. For more information, please send contact:
    Institute of Caribbean Studies.

  • Suad Awil

    I think that destroying the coral reefs in the Caribbean are terrible because the Coral reefs are so beautiful and natural
    it also attracts tourists to the Caribbean.
    Also Most of the coral reefs are dead anyway !!!!

  • Derek Bickerton

    I notice your report contains no mention of Cuba. On 1/23/15 in Science Friday NPR aired an interview with David Guggenheim, founder of the nonprofit Ocean Doctor which promotes marine research, in which he pointed out that while coral in the rest of the Caribbean was dying, in Cuba it was flourishing and in places even increasing. Since most if not all the factors suggested in the IUCN report are present in Cuba as well as the rest of the Caribbean, this is quite baffling. The only explanation that make sense is Guggenheim’s–that while, due to development, toxic runoff from pesticides and other pollutants has increased exponentially elsewhere, Cuba’s political isolation prevented the emergence of mass tourism and, especially after USSR subsidies ceased in 1993, has forced Cuban farmers to greatly reduce or abandon their use of pesticides and fertilizers, reducing the flow of pollutants into Cuban coastal waters.

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