Listed below are the major hazards divers and snorkelers encounter on the Great Barrier Reef. We urge you to utilize the wealth of local knowledge of the skipper and dive masters on your boat. They know the dive sites, what hazards are found on each of them, and how to best reduce the risks. Listen to their advice and ask questions if you are uncertain about any hazard or precaution.
If you are stung or bitten report this immediately to the dive master, some venomous stings, while not immediately painful, can become quite serious minutes later. A cut or a bite can become infected if not cleaned well. The dive staff is trained in first aid for each type of sting, (treatments do differ, and are constantly being improved.)
Many of these risks can be avoided by the simple dont touch rule. If you control your buoyancy and position in the water, and avoid touching the bottom or the reef, the chances of a scrape or sting are reduced dramatically
You are the key element in reducing your risks diving and snorkeling anywhere. Trust your good judgment, and know when to rely on your dive masters local knowledge
- Know how fit you are, and know your limits. Dont overexert yourself.
- Know how long it has been since your last dive, and consider taking a guided dive, a refresher course, or getting re-certified if you feel in need of it.
- Plan a safe dive, and follow the plan.
- Know the hazards and how to avoid them.
- Know how to use your equipment safely, and always do a safety check of your equipment before each dive.
- Pay attention to any information given in the pre-dive briefing by the dive staff, follow their advice, and ask questions if you dont understand something.
Things that sting
Crown of Thorns: These interesting sea stars eat coral, and at times hit populations that can damage a coral reef. They are covered with long venomous spines, and the way they look it should be easy to follow your instincts and avoid touching them
Sea Urchins: Many of the species here have shape spines, and we have read of species that can also inject a toxin. As with all reef life, avoid touching them
Fire Corals: These can inflict a very painful sting. Avoid touching branched corals, and you will avoid their sting
Stinging Hydroids: If you follow the don't touch rule you will avoid contacting these interesting organisms, who can inflict a very painful sting.
Stinging Jellyfish: There are several species jellyfish found here whose sting could be life threatening. The nets you see along the beaches during the summer months are to protect swimmers from one kind that is found along the coast. Out on the reef there is a species or set of species whose sting/venom can cause what is called Irukanji Syndrome, which can be life threatening. During times when risk of encountering these very small jellyfish is higher your dive operator may recommend you wear a lycra stinger suit, which drastically reduces your risk of being stung. Always follow (or exceed) the advice of the dive staff regarding this animal.
Anemones are closely related to jellyfish and corals, and like them are armed with tiny stinging cells. Thankfully most anemones are harmless, but some can deliver a painful sting. Avoid touching anemones
Stinging Fish: Lionfish, Stonefish, and certain other reef fish have spines in their fins that contain venom and can puncture you and inject the venom. Some of these fish are very well camouflaged, so avoid touching the reef, and use care when touching the bottom, and dont annoy lionfish when you encounter them swimming.
Cone Shells: Cone shells are predatory snails, and kill their prey (usually fish) by shooting a toxin-loaded dart into them. Their handsome cone-shaped shells are very easy to spot, and under no circumstances should you pick up such a shell; a seemingly empty shell may just have the animal fully withdrawn into it. Certain species have a deadly toxin
Sting Rays: Rays are beautiful organisms, but do have a barbed spine at the base of their tail. Divers are rarely jabbed by these spines, almost always when the step, kneel, or sit on a ray hidden in the sand on the bottom. If you do find a need to rest on the bottom, shuffle the ends of your fins gently in the sand to give any ray under the sand a chance to swim off.
Things that bite
Sharks, Morays, and other large fish: Bites by sharks and other large fish are uncommon on the reef, and are usually associated with fish that are being fed, or fish that have become accustomed to being fed. If you are diving where sharks and other fish are being fed, follow the instructions of the dive master, they have experience with the animals that come to be fed and know how to reduce the risk of being bitten
Sea Snakes: Sea snakes are extremely venomous, but not prone to wasting their venom on items that they cannot eat. They are not known for aggression most bites are defensive, handling or annoying these animals is definitely out. Certain dive sites are known for being likely places to encounter sea snakes, ask your dive master about what to do if you should encounter one of these beautiful animals
Smaller Fish: During breeding season (the summer months) certain reef fish (especially triggerfish) pair off and aggressively protect their nests/young. With the breeding hormones raging these fish are not easily intimidated, and occasionally a diver gets bitten on the finger or ear. If some smaller fish comes after you, it is telling you to get out of its territory, follow the fishs advice and move away.