Forget Shark Week, Jellyfish Are the Real Killers of the Sea

The Discovery Channel does a great job of hyping up how dangerous, mysterious, and overall cool sharks are during their annual Shark Week special, but why isn’t there a “Jellyfish Week?” These brainless blobs kill far more people around the world every year than sharks, stingrays, and sea snakes combined, yet jellyfish still don’t get the recognition they deserve for being the true toxic man-killers of the sea.

They’re brainless, bloodless, and heartless, but the simple box jellyfish “Chironex fleckeri” usually kills one unlucky swimmer off the coast of northern Australia, 20 to 40 in the Philippines, and around 100 scattered throughout Southeast Asia each year, and that’s only the confirmed fatalities… Box jellyfish were creatively named for their cube-shaped bells, sport 15 whip-like tentacles that stretch up to 10 feet long, and are covered in millions of microscopic dart-like structures that can easily pump enough venom into their victims to kill up to 60 adult humans at once.

Also known as the “sea wasp,” box jellies normally utilize their incredibly potent venom to sting and instantly debilitate fish and shrimp so that their potential prey doesn’t get an opportunity to damage their relatively fragile tentacles. Although that feature is excellent for grabbing a meal and keeping predators at bay, the fact that many box jellyfishes are nearly crystal clear often puts them in the path of unaware swimmers.

If you were to be stung by a box jellyfish, aka the most toxic jellyfishes on earth, you would instantly feel a deep, searing pain that has been consistently compared to “a red hot iron” along the areas that the tentacles touched your flesh. If you don’t go into shock and die from a heart attack or drown because the only thing you can focus on is the intense pain and manage to haul yourself back to shore for immediate treatment, the burning agony of the sting can persist for weeks and you can look forward to some nasty whip-like scarring along the wound.

While that particular box jellyfish is the clear leader when it comes to killing humans, other box jellies, and the tiny Irukandji jellyfish, in particular, torment their victims long after they’ve left the water by inflicting Irukandji syndrome along with their stings. Irukandji jellyfish are barely over an inch wide as fully grown adults, but if you’re hit by the stingers that line the ends of their minute tentacles, expect to feel a combination of vomiting, severe headache and muscle cramps, nausea, anxiety, back pain, sweating, and what can only be described as “a feeling of impending doom,” where patients are completely convinced that they are dying. The various symptoms that come with the sting can linger anywhere from four hours to several weeks, and survivors claim that the actual sting from the little jellyfish feels no worse than a mosquito bite!

The good news is that most of the world’s jellyfish don’t even come close to their horrifying Australian cousins when it comes to toxicity, but that doesn’t mean that they won’t ruin your day if you bump into one. For instance, the nastiest jellies that Americans have to deal with include common six-foot-long sea nettles, moon jellies, and the world’s largest jelly, the lion’s mane jellyfish. The dome of a lion’s head jellyfish can grow up to six feet in diameter, and its hundreds of tentacles can extend 100 feet or more. As scary as running into this squishy behemoth sounds, the good news is that a sting from a lion’s head will only cause localized redness and short-term pain.

Well, that’s not to say that a lion’s head jellyfish can’t be a large-scale pain too; in 2010, a 50-pound jellyfish was discovered 100 feet from the shore of a New Hampshire beach, and when lifeguards attempted to bring it to the beach using a pitchfork, the jellyfish broke apart into many pieces in the water. The free-floating jellyfish chunks ended up stinging 150 people before they were properly disposed of, so let that be a cautionary tale about poking giant jellyfish with pitchforks.

I should also note that the infamous Portuguese man o’ war, known as a bluebottle in Australia, isn’t technically a jellyfish. Structurally speaking, a true jellyfish is a single animal, while a Portuguese man o’ war is made up of a series of specialized polyps that form the glassy blue and purple jellyfish-like creatures. I bring up this pretty non-jellyfish because they’re also a nasty problem for Aussies, as bluebottles are responsible for directly and indirectly stinging up to 10,000 people each summer. “How can one of these things ‘indirectly’ sting someone?” you may ask. The really creepy thing about these animals is that if their 33-foot-long tentacles become detached in the water and wash up on the beach, their powerfully painful stingers can remain active for days. If a bluebottle’s lengthy tentacle catches a swimmer, he will experience an overwhelming pain that lasts for a few hours, but the intense soreness is often accompanied by fever and shock, which may in some cases, lead to organ failure and death.

So what do you do if you’ve been stung by a jellyfish? Whoever came up with the solution of urinating on jellyfish stings may be lost to time, but don’t even consider that outdated “remedy.” It’s just gross — end of story. It will seem obvious at the time of the sting, but carefully remove any tentacle pieces that are attached to your skin by rinsing the area with sea water or scraping it off with a credit card. Next, you’ll want to rinse out the wound with salt water or vinegar. This will help to deactivate any remaining stingers. Finally, soothe the area with hot water, ice packs, and take some pain medication— jellyfish stings hurt!

To recap, about five people are killed by sharks each year, while at least 150 or so are taken by the spineless terror of the deep with their vile venom and twisted tentacles. Jellyfish might have a cutesy name and a pretty exterior, but the next time you’re at the beach and someone complains about “how scary sharks are,” just consider the transparent threat mindlessly bobbing under the waves…

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