Dangerous Marine Life & How to Stay Safe

Urine on a jellyfish sting: why it does not work, and what does

Of all the beach folklore, one piece has survived every attempt to kill it, and a national ocean agency has taken the trouble to write it down as a myth.

NOAA lists it under the heading “MYTH #3: Applying urine to a jellyfish sting can reduce the pain”, and the finding is flat: “the use of urine to treat stings has been tested and proven unhelpful. A better idea? Try an acidic liquid like vinegar.”

The sequence it gives instead is short enough to remember on a boat: “First, look for any tentacle adhering to skin, and flush the area well with cold ocean water. Do not rub the sting area because you could inadvertently distribute the venom further into the body. Then vinegar or evidence-based commercial product should be applied if there is continuing pain.”

Two details in that worth noticing, because they are the ones people get wrong in the moment. Cold ocean water, not fresh, fresh water changes the pressure around undischarged stinging cells and can set them off. And do not rub, which is exactly what a hand reaches to do. A small bottle of vinegar in the boat bag costs nothing and settles the argument on the day.

FAQ: marine life safety

How do you stay safe around marine life?

The golden rule is look, don't touch: almost every marine-life injury happens because someone touched, stepped on, cornered or tried to handle an animal. Control your buoyancy so you don't contact the reef, watch where you put your hands, knees and fins, never chase, feed or harass animals, wear exposure protection (even a rashguard), and shuffle your feet in shallow sand to avoid stepping on stingrays. Respect the animals and most dangers disappear.

What is the most dangerous thing when diving or snorkeling?

Statistically, the real risks are things like drowning, running low on air, currents and poor buoyancy far more than animal attacks, which are rare. When marine creatures do cause harm it is usually a defensive sting or bite after being touched or stepped on, not a predatory attack. So the biggest safety wins are good training, buoyancy, watching your air and conditions, and simply not touching things.

Are sharks dangerous to divers?

The vast majority of sharks divers encounter are not a threat and are a highlight of the dive, not a danger. Serious incidents are very rare and usually involve specific circumstances. Do not chase, corner, feed or harass sharks, keep calm, maintain eye contact, and follow your guide's briefing. Treat them with respect and enjoy them; they are far more valuable alive and undisturbed.

What should you never touch underwater?

As a rule, nothing, but especially avoid coral (including fire coral, which stings), anything with spines (lionfish, scorpionfish and stonefish have venomous spines), cone snails (a sting can be very serious), jellyfish and hydroids, sea urchins, and the small but highly venomous blue-ringed octopus. Also never put your hands into holes or crevices where moray eels or other animals shelter. When in doubt, keep your hands to yourself.

What is the basic first aid for a marine sting?

It depends on the animal, so follow local and professional guidance, but general principles include getting out of the water safely, seeking help, and for many venomous fish spine injuries (like lionfish or stonefish) immersing the area in hot (not scalding) water can ease pain while you get medical care. Some stings need specific treatment and some are medical emergencies. Carry the local emergency number, know where the nearest medical help and, for divers, the nearest chamber and DAN contact are. For anything that needs treatment, seek professional care.