All over the world, these little blobs with tentacles swim around the oceans and seas, terrorizing surfers, swimmers, and beachgoers that they encounter.
Okay, maybe terrorize is too much of a harsh word, especially when jellyfish aren’t even aggressive, compared to nature’s other ocean predators like sharks. Jellyfish usually just float around the water, seemingly uncaring about whatever events are occurring near it.
But if there’s one thing people remember a jellyfish for, it’s their sting. Stories of beachgoers looking to enjoy splashing around the sea for a short time, only to find their arm or chest in immense pain after coming into contact with the tentacles of a jellyfish are not uncommon.
But are they so dangerous to warrant warnings from lifeguards, such as when a jellyfish bloom (meaning, a time when the jellyfish population in the area is exploding) is occurring if the stings aren’t fatal?
Well, it’s a little bit more complicated than that.
Why aren’t jellyfish aggressive?
We mentioned earlier that jellyfish aren’t actively seeking out humans to attack and sting, and you may be curious as to why that is.
It all comes down to their biology.
Jellyfish are actually considered as planktons, which might come off as a surprise since most people see planktons as tiny, microscopic organisms that the naked eye can’t see.
But it actually fits them perfectly; jellyfish aren’t exactly strong swimmers. While they can control their vertical movement, they are at the mercy of the currents of the ocean, wherever it may lead them to with horizontal movement. This is because they have no bones, heart, or brain. In fact, a jellyfish’s body is 95% water!
So why do they sting? Certainly not out of malice. Their nervous system is so simple that they simply act upon their own species’ programming, and not because they want to defend themselves.
Comparing a jellyfish to a bee wherein both stinging out of self-defense is an incorrect assumption. The jellyfish is too simpleminded for that. While it does sting humans, it is because humans are touching places on a jellyfish where they shouldn’t be touched. They’re practically programmed like biological mousetraps. If you touch a certain part of the jellyfish (aka, its tentacles), then its body will react in response by stinging the offender. A jellyfish won’t go after you because it is hungry, nor will it go after you because it is territorial and you’re too close to it. It simply reacts according to the environment and other animals that are near it.
So yes, don’t worry about being chased by a jellyfish if you see one while swimming in the beach, it’s not going to chase you at all. Simply avoid touching it and you should be fine.
How a jellyfish stings
Contrary to what it might seem, a jellyfish sting doesn’t “shock” you in the same way electricity does (you would be forgiven for thinking this way, especially if you watched something like Spongebob growing up).
Instead, like a bee or wasp sting, a jellyfish sting releases venom into your body.
They way this works is that jellyfish tentacles already contain microscopic barbed stingers, so despite looking smooth, they simply have stingers that are too small for the naked eye to see. Each stinger found here has a tiny bulb, and said bulb contains venom and a coiled, sharp-tipped tube, which helps it to penetrate its target.
The trigger comes from the surface: Even simply brushing upon a tentacle is enough to cause it to release the stinger to penetrate your kin and release the venom it holds inside.
It is for this reason that jellyfish tentacles that are detached or found on the beach can still sting despite not being “alive” anymore.
Is there a jellyfish strong enough to kill a human person?
This is the million-dollar question. Many people around the world get stung by jellyfishes each year, usually out of carelessness from the presence of jellyfish, but many come out of it unscathed. Well, not really “unscathed” because they’ll still be suffering horrible burns from the venom for a while, but such pain will eventually dissipate over time.
But what about other jellyfishes? Is it possible that there might be a jellyfish out there that can kill a human person with its sting?
Jellyfish come in all shapes and sizes. Of course, as a result, this means that how powerful their venom is can vary wildly depending on the species. In fact, there are some species of jellyfish out there that don’t even sting, such as the moon jellyfish!
Unfortunately, the opposite is also true. Some jellyfish are so dangerous that their venom is potent enough to kill humans, instead of simply leaving a stinging welt. The box jellyfish, for instance, is likely the most dangerous jellyfish of all, as their sting is extremely painful, and for some species, quite possibly fatal to humans. They even have the reputation of “most venomous creature” in the world!
It is for this reason that paying attention to the lifeguards or the places where you are swimming is important. While jellyfish in general don’t pose too big a threat since they aren’t active aggressors, one can easily touch them by accident especially when they are swimming and their arms or legs bump into such a creature. You can only hope that the jellyfish that stung you wasn’t a box jellyfish if so.