Bleached skeletons:  Rising sea temperatures have killed coral on a large scale. An innovative project is under way in the Maldives to propagate the coral. Picture: SUPPLIED
Bleached skeletons: Rising sea temperatures have killed coral on a large scale. An innovative project is under way in the Maldives to propagate the coral. Picture: SUPPLIED

More than 90% of the coral that makes the Maldives such a magnet for tourists died in the past year in the quiet decimation of global warming.

Bleached and broken coral now lies on the bed of the Indian Ocean in the beautifully clear but lethally warm water.

It is a global crisis, with parts of Australia’s iconic Great Barrier Reef also heavily damaged.

"Last year [2016] was one of the worst bleaching events on record," says Dr Camilla Floros, a scientist on the Reef Biodiversity Programme run by the Oceanographic Research Institute in Durban. In the Maldives, marine biologists from marine consultancy Seamarc are working to reverse the damage with an innovative method of coral propagation. Tourists can lend a hand by physically helping with the work or by sponsoring a patch of regenerated coral reef.

These ocean experts are working with Club Med Kani, a resort where social responsibility and sustainable tourism is as much a part of the ethos as pina coladas and party nights.

Marine biologist Stephen Bergacker pulls fingers of healthy russet-coloured coral out of a bucket of seawater. He has broken them off a healthy reef a few minutes earlier and now ties each fragment onto a dome-shaped metal frame.

Clipping them on with cable ties looks rather primitive, but it is the best way to fix shards of coral onto their new home. As he works, holidaymakers stroll over to hear about the ravages of global warming and help to tie on more coral.

When the frame is covered, Bergacker picks it up, walks along a jetty and flings it into the ocean, where it settles near a handful of other frames on the ocean bed a few metres beneath the surface.

There are 5,000 of these man-made coral crèches scattered around the Maldives, with more added every day. "We choose sites with good conditions for growth and we’ll place about 800 frames together there in clusters," Bergacker says.

For the first two weeks, the coral is too traumatised from being broken and relocated to do anything except recover.

Then it begins to grow again, and after two years, the frame should no longer be visible beneath a vivid cluster of colourful coral, which has been attracting fish and other marine life back to areas that global warming has destroyed.

Coral is made by tiny living creatures that create a calcium carbonite skeleton to protect their soft bodies.

Trillions of these tiny animals create the coral reefs, which are the aquatic equivalent of rainforests. "The reefs are so important — only 0.01% of the ocean floor is reef, but it contains more than 25% of the ocean’s diversity," Bergacker says.

Distressed

Coral forms a symbiotic relationship with algae called zooxanthellae, which give the coral its colour and 80% of its energy through photosynthesis.

When coral is distressed through rising temperatures or by being damaged in other ways, the algae generate such toxic levels of oxygen that the coral ejects them, losing its colour and energy.

If the temperature drops back to normal the algae return and the coral recovers. But if the water stays too warm for too long, it starves to death.

Seamarc has been propagating coral in the Maldives since 2005, but in May 2016, El Niño turned up the heat and 90% of the archipelago’s coral was bleached. Sea surface temperatures hit a new high of 34°C and only corals living deeper than 12m went unharmed.

In SA, the best coral reefs are at Sodwana Bay, one the world’s premier diving sites with reefs even further south than the Great Barrier Reef.

That southerly position has been the reef’s saviour from global warming.

"The reefs have not been as badly affected by bleaching as the Maldives and Great Barrier, for several reasons," says Floros. "They are subtropical reefs so the water doesn’t reach such high temperatures as on tropical reefs, and our reefs are deeper so they aren’t exposed to such high solar radiation, both of which are major causes of coral bleaching," she explains.

Despite the catastrophic bleaching elsewhere in 2016, only 10%-13% of SA’s coral community was bleached, she says.

"We are not conducting any coral restoration projects on our coral reefs at the moment, largely because our reefs have not been as negatively impacted by threats such as global warming, diver damage and overfishing as many reefs in other parts of the world have," says Floros.

"We are very lucky because our reefs have high coral and fish diversity. The coral is in a healthy condition, with low levels of disease, bleaching, crown-of-thorns starfish and diver damage," she adds.

The Seamarc programme is one of the world’s most successful coral reef propagation schemes, but its marine biologists now have to dive deeper than 12m in the Maldives to find good coral to transplant to other areas. They only take cuttings from the edges of a colony and leave the centre untouched.

Some people criticise the method because it involves breaking off healthy coral, but it is just like transplanting a tree and allows one colony to generate many others, says Sebastian Stradal, manager of Seamarc’s Marine Discovery Centre. "It will still regrow without our intervention, but we are trying to make it grow faster and spread more awareness about coral bleaching," he says.

The frames are monitored regularly to record the growth, and are often repositioned to deeper, cooler areas of water. Photos taken every six months are posted to Seamarc’s website, so people sponsoring a frame can see the progress of their personal coral patch.

The sand-coated domes of thin metal are made in a local village, creating jobs for five former fishermen who have witnessed global warming destroy the fish population.

The tactic could be replicated globally, especially if Club Med rolls it out to its resorts in other areas where coral has been damaged. It makes sense, as tourists in search of excellent diving and snorkelling need vibrant reefs, and can help to rebuild them.

"Environmental protection projects like coral propagation can be tied into the guest experience," says Lisa Bedez, a sustainability co-ordinator who helps each resort to qualify for Green Globe sustainable tourism certificates, provided by a private programme, through eco-friendly practices.

"In six months, you’re not going to have a great reef, but you can put a lot of frames together and it looks like a natural reef and the fish come back to repopulate the ecosystem."

Please sign in or register to comment.