Marine life stings are an uncommon, but an unfortunate reality of exploring the aquatic world. No matter how hard we try, we cannot entirely eliminate the risk of marine life stings for ourselves, or those around us. Know how to mitigate the risks, treat the injuries, and keep yourself sting-free and happily diving this season.
Jellyfish
The name “jellyfish” refers to an enormous number of marine animals belonging to the phylum Cnidarian. While some specific species, like Box Jellyfish, can cause life-threatening health complications with their venom, the majority of jellyfish encountered by divers will be significantly less lethal.
Jellyfish stings typically range from painless, imperceptive numbness, to burning reactions with mild or moderate blistering. It’s easy to become too task loaded to keep an eye out for jellyfish, so remember to keep a close eye on your surroundings and provide dive skins or wetsuits to protect their skin.
In locations where the jellyfish populations are particularly prominent, it is possible to be stung by almost invisible strands, or pieces of strands, of tentacle carried in the current – mechanical protection like a dive skin is your best bet for injury prevention in these areas.
Should you or a buddy be stung, irrigate the area with generous amounts of vinegar to prevent further envenomation, remove any visible tentacles with tweezers or protective barriers, and wash the area with a seawater or saline solution. Irrigating with freshwater can cause further envenomation. Using painkillers, anti-inflammatory medications, or topical anesthetics can help remedy discomfort, as can immersing the area in hot water, or icing the injury for 30-90 minutes.
Life threatening reactions are rare, but possible, and are characterized by severe pain, nausea, vomiting, shortness of breath, muscle spasms, low blood pressure, dysrhythmias, and cardiovascular failure.
Box Jellyfish | Prevention
- Properly research the areas you intend to dive.
- Avoid known box jellyfish habitats if you are not sure the dive site or swimming area is safe. If you are stung, cardiovascular stability can rapidly deteriorate with very little time for any effective field intervention.
- In Northern Queensland, Australia, net enclosures are placed in the water where box jellyfish are known to be during summer months (November to May), but these cannot guarantee safety.
- Minimize unprotected areas. Always wear full wetsuits, hoods, boots and gloves. Something as simple as nylon pantyhose worn over the skin will prevent jellyfish stings.
- Carry sufficient household vinegar with you to all dive sites.
- Always look down while descending.
Fire coral
Fire coral are colonial marine cnidarians that can envenomate humans through direct skin contact and cause burning skin reactions. The coral often appears yellow-green or brownish and frequently has branchy formations, although this can vary based on its environment. Divers can avoid injury with fire coral by avoiding contact, or using mechanical protection like a dive skin or gloves.
Fire coral injuries typically present as a burning sensation that can last several hours, followed by a rash that may last for several days. The rash will often subside after a day or two, only to reappear several days or weeks later. Treat fire coral injuries by rinsing the affected area with vinegar and keeping the area clean, dry, and aerated. Redness and vesicles will likely develop – allow the injury to heal on its own and do not irrigate the area further or puncture the vesicles.
Fire coral injuries are rarely serious, but can complicate open wounds and result in tissue death, so be sure to seek qualified medical attention if you or a buddy has a rash in the area of an open wound.
Fire Coral | Prevention
- Properly research the areas you intend to dive.
- Avoid known box jellyfish habitats if you are not sure the dive site or swimming area is safe. If you are stung, cardiovascular stability can rapidly deteriorate with very little time for any effective field intervention.
- In Northern Queensland, Australia, net enclosures are placed in the water where box jellyfish are known to be during summer months (November to May), but these cannot guarantee safety.
- Minimize unprotected areas. Always wear full wetsuits, hoods, boots and gloves. Something as simple as nylon pantyhose worn over the skin will prevent jellyfish stings.
- Carry sufficient household vinegar with you to all dive sites.
- Always look down while descending.
For more information on marine life injuries, review DAN’s Dive Medical Reference Book on Hazardous Marine Life Injuries.