This winter, thousands of British travellers will visit coral reefs all over the world, from the Red Sea to Indonesia and the Great Barrier Reef. Yet the world's coral reefs - the "rainforests of the sea" - are under imminent threat. According to the World Wildlife Fund, 27 have been destroyed and, if present trends continue, 60% will be lost in the next 30 years.
While the most significant threat to coral comes from pollution, over-fishing and climate change, bad scuba diving practices can cause significant damage to these fragile ecosystems. The key to all good diving is buoyancy control - the more in control you are the less likely your fins, hands, knees and scuba equipment will bump against the coral and damage it. On average, it takes 25 years for coral to recover from a diver's single clumsy brush against it. Too many divers at a site can also cause disturbance to fish and the coral, so check that your dive operator avoids the busiest dive sites. Responsible dive operators should also have a policy of anchoring only to permanent buoys (attached by concrete to the sea floor) rather than dropping anchors on or near reefs.
PADI (padi.com) runs a course on protecting the marine environment and a Peak Performance Buoyancy course, which both count as "speciality" courses required for the Master Scuba Diver certification. It also runs Project Aware (projectaware.org), which organises underwater conservation activities.
And you can put your dive holiday to good use by contributing your underwater observations to the Global Dive Log (earthdive.com).
· To ask a question or offer advice, go to greentraveller.co.uk.