Ask any diver to tell you about the Portuguese Man-of-War, and they will probably wince, regardless of if they’ve ever actually encountered one. This sea creature has a well-deserved reputation of delivering brutal consequences to the unlucky victim who strays into its streaming tentacles. The venom injected from the tiny barbs on its tentacles have caused the deaths of at least three people, and victims usually bear lasting physical scars, reminiscent of jagged lightning where the tentacles have come in contact with skin, never mind the emotional and psychological impact!
But despite their evils, these marine organisms are actually quite fascinating. A common conception among the non-diving public is that the Portuguese Man-of-War is a type of jellyfish, which is false. It is actually a colony comprised of millions of organisms, each responsible for a function of the entire colony’s survival. These animals are called siphonophores, and their large order includes creatures like pyrosomes and corals. In the case of the Portuguese Man-of-War, there are four separate colonies working together:
- Sail This is the part of the animal that resembles a balloon, allowing it to float on the surface in the ocean breeze. It operates much like a human lung, taking in gas that is secreted by another colony in order to stay afloat. An integrated siphon allows the Man-of-War to quickly expel the gas and submerge briefly.
- Defense There are three additional colonies of polyps that watch over three distinctive tasks, yet are all bundled together in an indiscernible pattern. The defense colony is comprised of the long, trailing tentacles that are typically about 30 feet in length, but have been recorded at lengths up to 165 feet! These are the tentacles to beware of, since they serve as the Man-of-War’s “fishing” tackle. Fish and other creatures that are small enough to get entangled meet their demise at the ends of these deadly tendrils.
- Feeding The defense tentacles have contractile cells that pull the prey in closer to the feeding colony. These tentacles are shorter and clustered together, and once the prey is within range, each tentacle surrounds the body and begins secreting enzymes to break down and digest its nutrients.
- Reproduction This colony’s sole responsibility is reproduction, and therefore these are the shortest tentacles of all, protected among the longer and stronger colonies that surround it.
Portuguese Man-of-War slayer - Glaucus atlanticus
These graceful killers inhabit many of the world’s tropical regions, and their carnivorous nature often puts them in the path of unsuspecting swimmers and beachgoers year after year. It does have a few natural predators, like the loggerhead sea turtle and a certain type of nudibranch, but it is not uncommon to have many of these creatures wash ashore in summer months. It is important to note that the vinegar cure for most jellyfish stings will not work, and medical attention must be sought quickly. Rather, apply salt water and very hot water to the affected area. The heat will help to neutralize the pain by denaturing the toxins. If you see one washed up on the beach, take a good look at it, but don’t touch it or step on it to avoid any accidental injuries. Their venom can remain active even when the animal has been washed up for days!
Images via Jayjay P, tarotastic
I’ve seen them wash up in Hawaii on the other side of Maui, and I watched carefully where I placed my bare feet. My answer is NO and I don’t want to find out.
The Man o War is a nasty stinger for sure…good information save one issue..
I would beg to differ with you about the application of vinegar as there is no fact based science that suggests vinegar does not work…well, objective science rather than self serving commercial claims or “reviews” done without field trials ….Dr Paul S Auerbach, a leading authority on envenomations including that of the MOW recently published his 7th edition “Wilderness Medicine” book which recommends the use of acetic acid on the man o war. after multiple field trials..I have used vinegar and watched it used and it provides the pain relief and meaningful first aid without the use of topical anesthetics…While controversial, I will use acetic acid on all marine stings because it has proven for years to work very effectively…gl and safe diving..BL
Yes! They sting and the stinging sticks around for a little while!
Had one wash into me by a wave while waiting for the boat to pick me up. Their tentacles are yards long and the sting looks like a burn mark for days after.
yes in the FL keys. left whip marks.
I’ve seen small ones in Hawaii and bigger ones in Florida. I’ve been told to run sand on the area, and that seems to take some of the stingers or whatever away. Does anyone know if when their bubble is popped if the thing dies faster?
Interesting!
I dont get close enough to burst theyre bubble. Im one of the unfortunates that is allergic to stinging things. From bees to sea robins to jellys.
Been stung a few times while tending divers umbilical off the louisiana coast, I’d recommend gloves!
We get them all the time in australia, depends on the season and winds somtimes the beach will be littered with them
I agree with Danny. You haven’t really been swimming at an Australian beach until you’ve been stung by one. It’s part of growing up here
Bumped into one as kid while staying on S. Padre Is.,Tx. Only got stung on the knee.
They fill the south Florida south east coast all the time… Went out surfing one day and as I paddled out my arm swept right under the bubble and right into the stingers… Needless to say the sting wasn’t enjoyable but could’ve been worse. Best trick is to use the sand and rub it on the skin to scrape off the tentacles if still on and some vinegar if stinging still occurs! Be safe!
Portuguese Man O War. All over the beach in south Florida after a storm. Sting is bad. Takes hours to go away. They shoot a microscopic dart into your skin called a nematasist.
To Andrew Wight….the answer is no. The stinging cells are seperate from its mantle. A PMW can be high and dry for days and still have active cells.
Man from hell is what I call them, we have them down here in Miami. When stung very painful and leaves a nasty mark and leaves a itch behind like you wouldn’t believe. But there very beautiful and attractive, the average kid would see this floating on the shore or even dead along the sand and will get a unpleasant surprise once it’s picked up!!!! Vinegar or urine didn’t help at all.
My girlfriend and I got stung on Saturday. She had it wrapped around both of her arms. Very painful.
Thanks for the lesson. Even National Geo says they are part of the jelly family. My encounter was a silly mm away from the mane, behind me! TX again to my good buddy.
Dorothy, they are in the same phylum as jellyfish, but are in completely separate orders. PMW share a phylum with not only jellyfish, but also sea anemones, corals, and sea pens, to name a few.
In australia they recommend not using vinegar on these as it will burn, best get the sting out, salt water will help neutralise and then ice, and to use vinegar on jelly fish stings
Yes, I got stung by one back in the late 80′s when one washed up on a little beach on the South Shore of Nova Scotia. It hurt like hell for a few days.