THE ever-increasing number of scuba divers and snorkelers is leading to growing concerns about the amount of damage these plungers cause to coral reefs. Underwater recreational activities, including both scuba diving and snorkelling, allow us to explore the amazing underwater world and its huge variety of marine creatures. But what about the impact of these activities? It seems that we need to give serious attention to improve our diving – or snorkelling – skills and managing our behaviour underwater.
Generally, increasing reef contact and damage were highest among “unlimited diving” groups and unsupervised day and night dives. It was reported that divers using cameras have significantly more contacts with the reef than those without cameras (1.6 breaks per 10 minutes versus 0.3 breaks per 10 minutes). Imagine the damage done by a group of unsupervised divers with cameras, diving for about 50 minutes. How much more damage can our remaining coral reefs take?
Various studies have been conducted to assess diver impact by following divers, observing their underwater behaviour and recording reef damage. The studies identified the following major contacts made by divers and some snorkelers:
▶ Finning/kicking against the bottom
▶ Kneeling/standing on the bottom
▶ Clutching/holding corals
▶ Touching corals
▶ Dragging equipment
How do these activities cause damage? Fin kicking is the greatest threat as it causes breakage and abrasion of living corals and reduces visibility from the stirred up sediments. Even though these impacts may be unintentional, the impact to the coral reef can be lethal and the injured corals may take years to recover. The studies also noticed that some divers hold onto corals while diving in strong currents or to gain control of their movements.
But how much damage do divers really cause? The studies measured damage rate in “frequency of break/contact per minute”, and the amount of damage was found to vary widely among individuals. In a study conducted off the reefs of Redang, Malaysia, an average of 3.41 contacts were made per diver. This amounts to 11,000 contacts per year. Eighty-three percent of these contacts were made on living coral.
What can you do to save the coral reefs?
▶ Be a responsible diver and snorkeler – practice good buoyancy control, never harass or touch marine life
▶ Be a responsible underwater photographer and videographer – avoid contact with the bottom, check the surroundings before landing if you must, and land only on sand or dead corals but not LIVE corals
▶ Be an EcoDiver – take up the EcoDiver training course and participate in coral reef surveys
▶ Support marine conservation – report observations or environmental issues noticed to the relevant authorities (dive shop, marine park, Reef Check, etc)
▶ Participate in environmental awareness programmes to help safeguard our marine resources
▶ Always remember: “Take only photographs and leave only footprints”