Coral Reef Kill Offs in the Maldives

Rising ocean temperatures are the bleach of death to once-brilliant sea wonders.
Warm temperatures kill off the symbiotic algae that lives within the coral and gives it color. (Photo: Jon Bowermaster)
Nov 18, 2011· 3 MIN READ
A six-time grantee of the National Geographic Expeditions Council, Jon writes about all things ocean.

There are few places on the planet as remote as the Maldives. Landfall is a thousand miles away from much of the long string of 1,200 islands, most of which are little more than thin, uninhabited strips of sand. Diving into the heart of a Maldivian lagoon, you can easily imagine you’re alone in a distant paradise.

Yet when I did just that a few days ago, in the heart of the Baa Atoll—463 square miles of aquamarine Indian Ocean recently named a UNESCO Biosphere Reserve—something didn’t feel, or look, quite like paradise.

The ocean, though jaw-droppingly beautiful, was a bathtub warm 86 degrees F. Diving to its shallow floor, I could quickly tell that the realm below sea level has been badly impacted in recent years by a combination of man and Mother Nature and resulting fast-warming temperatures.

The coral reefs of the Maldives were first badly damaged in 1998, when shifting ocean patterns associated with El Niño raised sea level temps above 90 degrees. The result then was that 70 to 90 percent of the reefs surrounding the Maldives 26 atolls were badly “bleached,” with warm temperatures killing off the symbiotic algae that lives within the coral and gives it color.

While many of the reefs have been recovering since then, according to a report by the Maldives-based Marine Research Center, another warming last year (2010) estimated that “10-15 percent of shallow reef coral is now completely white, while 50-70 percent has begun to pale.”

On this day I was diving with Fabien Cousteau, grandson of Jacques and executive director of Plant A Fish, and Mark Lynas, author and climate-change adviser to Maldives President Mohamed Nasheed. During our first dive along a shallow reef in the middle of Baa Atoll we repeatedly signaled “thumbs down” to each other, as it became clear that this reef was troubled. Blanched the color of cement, the coral tips were mostly broken off, leaving behind just bare rock.

Blanched the color of cement, the coral tips were mostly broken off, leaving behind just bare rock.

Maldives-based marine biologist Kate Wilson dove with us and explained recovery was slowed this past April when another bleaching event occurred, with high sea temperatures again sweeping the area.

Kate assures us there are nearby reefs less impacted by local fishing and closer to colder currents, which may help them recover faster.

I hesitate to paint an overly bleak picture of the Maldives because there are some very good things going on here too. Last year the island-nation became just one of two countries to completely ban shark fishing in its 35,000-square-mile exclusive economic zone (Palau is the other).

Tuna in the Maldives is limited to being caught by pole, one of the most sustainable forms of fishing. And the naming last year of Baa Atoll as an UNESCO Biosphere Reserve is significant, placing it along such sites as the Galapagos, Ayer’s Rock in Australia, the Pantanal wetlands of Brazil and Amboseli National Park in Kenya. The challenge now is to help educate the local populace about the reserve-status, help impacted fishermen find alternative employment and fund enforcement.

And more promising information: the next day we visited a reef in the center of the Baa Atoll, which showed signs of a strong recovery. It is dramatically different.

Just below the brightly sunlit surface hundreds of shiny reef fish darted and fed. In the deep, dark blue swim we saw the Maldivian big guys—jackfish, tuna and red snapper. An occasional spotted eagle ray elegantly flapped past us, as do a pair of green sea turtles.

During a mile-long swim we spied an incredibly beautiful and vast variety of wrasses, clown, surgeon and parrotfish. A dusky moray eel peeked out of its coral hideaway. And a square-headed porcupine fish attempted to hide itself deep inside a rock crevice. The shallow, sandy floor running to a sandbar was heavy with gray-beige coral, colorful clams and even a few handsome sea cucumbers.

On the way back to shore, we quizzed Kate about the future of the reefs and the Biosphere.

Where will the funding come to protect the new park? “The government and a half-dozen resorts that operate within the Atoll. Starting in January 2012 tourists are going to pay too, buying permits for things like sport fishing and swimming with the manta rays, which will all go into the management of the biosphere.”

Are some zones in the atoll already off-limits to fishing? “Nine core areas are strict no-take zones,” she says.

What about pelagic, open-ocean fishes like bluefin tuna—are they protected? “Since they are migratory species it is quite hard to manage them. Once they are out of Maldivian waters and into open ocean international fishing, fleets target them. So even though the Maldives fishery is one of the most protected, by sustainable fishing, stocks are still declining.”

Can the coral truly recover if water temperatures keep rising as they have been? “It’s a good test here to see just how fast corals can adapt. It’s not just about the temperature but also about acidification as well, so all of the corals are really at a critical point. No on really knows how quickly they’ll adapt, if at all. If we are not careful globally, what you’re seeing could become the new norm.”