The Most Important Thing To Avoid Doing If You See A Dead Jellyfish On The Beach

Few things out there can ruin a perfect beach day quite as much as an unexpected encounter with the local wildlife — especially a jellyfish. Although most beachgoers know to steer clear of these gelatinous creatures while swimming in the water, most people don't realize that jellyfish can pose just as much of a threat when washed up on the shore. Even more surprisingly: These translucent creatures can still pack a powerful punch (or sting) after they've died — all thanks to a unique biological defense mechanism.

In an exclusive interview with Explore, marine biologist Kristyn Plancarte — or @k_passionate, as she's known to her more than 1 million TikTok followers — revealed the science behind this persistent threat. According to Plancarte, dead jellyfish retain their ability to sting due to specialized cells called nematocysts, which operate independently of whether or not the creature's alive. "These cells are set to trigger on touch and not controlled by the animal," Plancarte explains. "When triggered, the lid of the cell will fly open and the coiled thread springs out and injects the toxin into whatever triggered it."

This autonomous defense system ultimately means that a jellyfish's tentacles can remain dangerous even after washing up on shore. So, whether you're jetting off on a tropical getaway or simply packing up the car for a beach day in your own city, knowing what to keep an eye out for when avoiding jellyfish in and out of the water can make the difference between a day of fun in the sun and an unexpected trip to the ER.

Thankfully, avoiding any unnecessary jellyfish encounters is relatively straightforward. For starters, one of the most important rules to remember if you happen to run into a dead jellyfish on the beach is simple: Keep your distance. While it might be tempting to poke or prod these alien-looking blobs, Plancarte, who shares educational and marine biology content on her YouTube channel, strongly advises against any form of physical contact. "People should avoid touching sea creatures dead or alive," she warns. "It can be dangerous not only to the person but to the animal as well!"

It's also worth noting that this guidance extends beyond just human beachgoers. It's equally important to keep pets — especially dogs, who rely on their nose to make sense of new objects — from wanting to investigate these creatures up close while enjoying a trot along the beach. This caution becomes even more critical if you're unlucky enough to run into one of the most dangerous species of jellyfish on a trip — which, luckily, doesn't happen often, but definitely can happen depending on where you are. That said, the best approach is to always give all marine life, living or not, plenty of space unless you're a trained professional. This respectful distance not only ensures your safety, but also helps preserve the natural beach ecosystem.

Successfully staying safe in and out of the water is all about being prepared and aware of your surroundings. However, despite all the precautions and best intentions, accidental contact with a jellyfish can still happen — and it doesn't mean you're completely out of luck. If you do happen to ever get stung by either a live or dead jellyfish, Plancarte has a simple step-by-step process that should take care of the pain and discomfort. First, carefully remove any visible tentacles using tweezers — never your bare hands. Then, soak the affected area in hot (but not scalding) water until the pain subsides. After the initial treatment, she also suggests applying hydrocortisone cream to help with any residual pain or itching.

Plancarte also helped dispel a common myth: "Under no circumstances should you pee on a jellyfish sting." Despite what popular beach folklore (and certain TV shows) might suggest, this advice actually has no scientific backing. In fact, using urine could potentially make things worse by triggering any remaining stinging cells to fire, which would only end up causing even more pain than you had to start with.

Finally, while most jellyfish stings aren't necessarily life-threatening, it's still important to monitor your reaction and keep an eye out for any complications that might start to come up after the sting. If you happen to develop any severe symptoms — like shortness of breath, skin blisters, nausea, or chest pains — the best thing you can do is try to take a photo of the jellyfish and seek out immediate medical attention.