Gulf Coast Beaches Feature

Decades of visitors' scuba-diving on Thailand's islands and reefs has had far greater negative effects on marine life than the 2004 tsunami. Considering that the number of visitors is quickly returning to pre-tsunami levels, every diver needs to be aware of, and consequently minimize, his or her impact.

As fascinating as something you see may be, do not touch anything if possible, and never stand on anything other than sand. Coral is extremely fragile, urchins are as painful as they look, and although sharks may be no threat to divers, you can appreciate the foolishness of grabbing one's tail. Other dangers to both you and the environment are less obvious: eels live within holes in rocks and reef; turtles are reptiles that require air to breathe and even some dive instructors are guilty of "hitching a ride" on them, causing the turtles to expend precious air. Let instructors know that you find this behavior unacceptable. Furthermore, don't feed fish human food —feeding the fish bread, peas, or even M&Ms may be entertaining, but it rewards more aggressive fish to the detriment of species diversity.

Divers should also make sure equipment is securely fastened or stored, so that no items are lost or scrape against coral. Divers should also maintain level buoyancy to prevent inadvertent brushes with coral, as well as to save air. Snorkelers who need to remove their masks should pull them down around their necks rather than up on their foreheads. Masks can fall off and quickly sink, and a mask on the forehead is considered a symbol of distress. When snorkeling, you can minimize underwater pollution by checking your pockets before jumping into the water. Conscientious divers can clip a stuffsack to their BCDs to pocket random trash they encounter. Lastly, it seems like a no-brainer, but apparently many people need to be reminded: don't flick cigarette butts into the water.

Sunscreen is a must anytime you are exposed to Thailand's tropical sun. Snorkeling unprotected is a guaranteed skin disaster (and painful obstacle to the rest of your holiday); however, sunblock, when dissolving into the water from hundreds of visitors each day, is bound to take its toll on the marine environment. You can limit the amount of sunscreen you must slather on by covering your back with a Lycra Rashguard or a short- or long-sleeve shirt while snorkeling.

Follow the credo: "Leave only footprints, take only memories (or photographs)." Try to minimize your impact on this ecosystem in which you are only a visitor.