Song for Jasmine

Anthias on the reef

Verena Wiesbauer is a marine biologist, with particular knowledge of coral propagation and restoration techniques. In March 2009, she gave a lecture to the Maldives Science Society. Someone in the audience filmed it, and was kind enough post it on google-video, so now you can all enjoy watching “The Coral Reefs of the Maldives” as I have.

I learned a lot from this presentation, it’s very educational and entertaining. There’s a ‘pop-quiz’ early on, in which you are asked to identify what type of plant or animal is being shown. I pride myself on having correctly recognised Coriocella (though I did have to look up how to spell it), having seen them in Baa Atoll a few years ago.

Verena tells us that the Maldives sits on a volcanic chain which forms the basement of the islands. These volcanoes were active around 67 million years ago, so around the time the dinosaurs were dodging asteroids. Coral first started growing on these volcanoes some 55-57 million years ago. Since then, sea-level has changed several times, most recently after the last ice-age when it rose dramatically as the ice melted and retreated. The Maldivian atolls were flooded at that time, and the upward growth of coral only succeeded in creating islands around 3000-4000 years ago. The actual coral growth in the Maldives now forms a layer about 2000 metres thick. That’s a lot of coral!

soft coral

Having shown us some of the animals that live in and around the Maldivian reefs, Verena goes on to tell us about some of the problems that are affecting the reefs today. Beach erosion is a serious problem. With two monsoons each year, coming from different directions, it is natural for the sand to shift from one side of an island to the other during the year. In 2000, half of the islands were sufferring from beach erosion. There are simple measures that the Maldivians can take to protect themselves from the worst effects of such erosian, such as not building too close to the shoreline and using sand and aggregates imported from India for construction (instead of dredged from their own reefs).

They can also protect the islands by protecting the living reef. A living reef will protect against beach erosion by reducing the force of the waves as they come inshore, a dead reef will soon be destroyed by the waves and offer little or no protection. A reef needs at least 50% live coral-cover to provide adequate protection, few of the Maldivian reefs have that at this time.

There are other threats to the reefs too. The Maldivians themselves generate a lot of waste, and they have nowhere to put it. The island of Thilafushi is a municipal landfill, and there is concern that all sorts of toxic waste from it may leak into the ocean and harm the environment.

gorgonian sea fan

Discarded fishing-lines cause a lot of damage too. One horrible slide in the presentation shows a turtle that became entangled in a fishing-line while it was young. It survived, and grew up with the fishing-line constricting its growth. I’ve never seen a turtle with an hour-glass figure before, and I hope I never do again.

Another major cause of damage to coral reefs is the tourist industry. Divers, even experienced ones, can cause a lot of damage. Verena gives a personal account of diving with tourists who lay down on the reef to watch sharks, and who were upset with her for not doing the same because she might scare the sharks away! I’ve seen divers who allowed their diving lamps to trail along the bottom of a reef like a wrecking-ball while they were concentrating on getting closer to a few manta-rays nearby.

Not surprisingly, divers with cameras cause more damage than those without, they’re focussed (literally!) on what they’re looking at, not what they’re bumping into. Diving from shore causes more damage than diving from boats, and night-diving causes more damage than diving during the day. Even without direct physical contact, reefs can be damaged by divers who kick up sediment with their fins, smothering the corals they have paid so much to see.

It’s not only divers, but also snorkellers, that damage reefs. Snorkellers will often stand on the reef to adjust their equipment, and can do a great deal of damage by careless contact. Verena cites a paper by W.R.Allison in 1996 which showed that snorkellers can can do an immense amount of damage in a short period of time.

Verena says that the dive-schools could give better briefings, for both divers and snorkellers. Her own experience is that people appreciate being reminded of the simple things they can do to reduce their personal impact. I know some dive-schools don’t like to impose on their divers, so will not mention such things in their briefings. You can always invite them to say something when they ask if there are any questions. Put your hand up and say “I have a question, do we have to be careful about what we touch on this dive?”. It’s worth a try!

Dive-schools should also respect the ‘carrying-capacity’ of dive-sites, and not visit them too frequently, so they have time to recover from each invasion. This is a particular problem in the Red Sea, where many reefs are seriously degraded by divers. Of course, that’s not easy when there are many dive-schools competing to take people to the most popular sites.

Individually, divers can take steps to reduce their impact even more. Those of you that dive with PADI can take the Peak Performance Buoyancy course (other organisations probably have something similar). You’ll find you dive better (i.e. use less air, are more relaxed) and do less harm to the reef because you have more control. You’ll see more on each dive, too, because you will spend less time fighting with your equipment and frightening fish with your thrashing, and more time looking around.

Coco-palm encourages tourists to preserve the environment

Tourism can also be a positive force. wildaid.org invented the slogan “When the buying stops, the killing can too“, and used it in their campaign against shark-finning. You can kill a shark for its fins only once, but if you leave it alive, tourists will pay again and again to come and see it when they dive.

Verenas’ presentation has an optimistic tone, she clearly loves her work. There are things that can be done to help the reefs, and she mentions some of the many restoration and conservation projects in the Maldives. She herself has assisted in the creation of an artificial reef at Huvafenfushi. I’ll end this post with a quotation she gave at the beginning of per presentation. It’s from Baba Dioum, a Senegalese environmentalist or poet (depending on who you ask):

It would be good if people were taught more about the world we live in today.

(Possibly) related posts:

1. Diving in the Maldives
2. The Maldives
3. Zemanta, and the Marine Conservation Society of the UK
4. What do you see in my blog?
5. Charles Darwin’s first theory of evolution

Tags: Maldives, PADI, Pollution, Reef Formation, Coral reef, Coral, Diving, Shark finning

Posted by Tony on Friday, May 1st, 2009 at 18:25 in Maldives, Pollution, Coral reef, Diving. You can follow any responses to this entry here via RSS 2.0. You can leave a response, or trackback from your own site.