Jellyfish have a complicated relationship with humans: They are often feared by beachgoers because of their sting. They can get unintentionally caught up in commercial fishing nets. Some jellies can even clog intake pipes of coastal power and desalination plants, and in high concentrations, can force closures of popular beaches.
For scientists, however, jellyfish are fascinating research subjects – they play important roles in the marine ecosystem and are a key source of food for some fish and sea turtles. Some even protect commercially valuable species, such as oysters, from predators.
Whatever your view may be, many misconceptions exist about jellyfish. Let’s bust the top three myths:
Myth #1: Jellyfish are all the same species
On the contrary, there are more than 200 documented species of true jellyfish (and many more of their stinging relatives) across the globe. The environmental conditions required for each species to thrive can differ. In fact, NOAA and Smithsonian Institution scientists recently found that sea nettles in the Chesapeake Bay are considerably different than those in the open ocean and recognized it as a new species.
Myth #2: Jellyfish go after people
Not true. Any contact with jellyfish is incidental. Humans are not on their menu, but when we are in their environment we can get in the way of their tentacles. While jellyfish don’t have a brain, they can sense light and have coordinated swimming behaviors, which help keep them in good places to hunt for microscopic plants and fish eggs/larvae, or other prey like fish, worms, and crustaceans.
Myth #3: Applying urine to a jellyfish sting can reduce the pain
Perhaps the most interesting of myths, the use of urine to treat stings, has been tested and proven unhelpful. A better idea? Try an acidic liquid like vinegar. There are also several commercially available products marketed for stings.
What to do if you get stung: 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.
Bottom line: NOAA busts three myths about jellyfish.
Members of the EarthSky community - including scientists, as well as science and nature writers from across the globe - weigh in on what's important to them. Photo by Robert Spurlock.