Meet one of the most eccentrically fascinating, yet obnoxious, animals in the sea.

By B. Naqqi Manco, TCI Naturalist
Photos By Marlon Hibbert and Eric Salamanca

Anyone who spends time in nature and gets to know our fellow earth inhabitants quickly learns that human manners, while shamefully rare within our own kind, certainly stop at our species’ borders. Even our “housebroken” domestic animals slobber, scratch, drink from the toilet before licking our faces, and do all other manners of despicable things. In spite of this blasé ignorance of human cultural mores, we love them.

Some wild animals are a bit too rude to be contained within our homes, so we leave them outside. Cows are lovely to see, but few will argue that they’d make good house pets. They’ll not only eat everything off the dinner table, but attempt to eat the tablecloth as well. Let us not fathom the train wreck of culture shock that would accompany any attempt to constrain a water buffalo or hippopotamus to the rigours of Emily Post.

One creature though, in this author’s opinion, easily obtains the prize for the single rudest animal on the planet. At least the organism in question is thoughtful enough to keep itself far out to sea and away from our kind, but any concern it may bear stops there. This spring, it has truly pushed the envelope of just how much ignorance may be countenanced from a member of the animal kingdom. While they normally only visit inshore waters of the Lesser Antilles in the late spring, odd wind patterns in 2010 may have brought them more northward, and in droves they have been paying unwanted visits to Turks & Caicos and Bahamas shores.

What are these odd creatures, and why are they being accused of such ill manners? Portuguese men-o-war (this is how the term is pluralised) are not, as is commonly thought, jellyfish. They are siphonophores — apologies, but there’s simply no common name for this eccentric group of animals. And group of animals they are: each man-o-war is a “they,” not an “it,” and comprises four separate types of animals that work together as one, each carrying out their respective share of the collective’s functions. One forms the float, a purplish blue membrane pumped full of air (mostly nitrogen but with extra concentrations of carbon dioxide or carbon monoxide) that can be anywhere from a few inches to a foot long. Mature floats have a flattened sail at the top over which this ridiculous creature has absolutely no control, other than having the ability to roll itself over to keep the sail wet when exposed to air (prevents the man-o-war from desiccation) and the ability to deflate it and sink into the water when conditions require this action. Despite being named for an Iberian war ship also known as a caravel, beating, reaching, and tacking are skills that evade these tragically poor yachters — they can only “broad reach” with the wind. The sail is oriented at such an angle that a man-o-war will drift 45 degrees to either the left or right of the wind, which functions to spread groups of them far and wide, and to colonise the world’s oceans for the last 600 million years.

Beneath the float and sail are three other members of the siphonophore collective. One manages all of the consumption and functions as the creature’s mouthparts and digestive track. Another sees to all of the colony’s reproductive needs, and produces sperm or egg which, when fertilised, divides asexually immediately into the prototype cells for the four types of animals that make up a man-o-war. Lastly, the parts that work for snaring food, and the parts that make the man-o-war, in my opinion, the singly most obnoxious animal in the sea, are its tentacles.

Man-o-war tentacles are long, thin, and brittle. They have the approximate texture of a strand of spider’s silk slathered thickly in snot, and typically dangle down 30 feet into the water column when relaxed, flowing in the current in hopes of snaring a fish or two. However, for some bluebottles, as these balloon-toting weapons of localised destruction are sometimes called, the tentacles grow to over 150 feet in length. Relaxed tentacles spread their blue pigment out in concentrated spots thought to mimic small sea creatures drifting in the water, which attract prey into the deadly net of tentacles. The tentacles are lined with microscopic, venom-injecting harpoons called nematocysts, each with a trigger slightly less stable than the temper of a recently bathed feral cat, and infinitely quicker-acting. When barely touched, the harpoons fire, not only injecting their venom, but sticking the tentacle to the victim so that more nematocysts fire.

When the victim is a fish, the function of this method is to more severely entangle and stun the fish, which is then hauled in and eaten. When the victim is a human, the nematocysts fire in their venom causing extreme pain along with all sorts of other undesirable reactions. These can include lymph node swelling, shortness of breath, days’ worth of red swollen rash, and even complete and final expiration. A swimmer tangled in 150 feet of man-o-war tentacles, all vying for a patch of innocent skin into which to inject their natural torture serums, can experience shock strong enough to drown, or can even die from the physiological effects of the venom itself. And just in case the man-o-war doesn’t get its point across while alive, the nematocysts can still actively fire for weeks after the darn thing dies.

Drifting through the sea, these long-tentacled menaces literally throw caution to the wind, and go wherever the gales and breezes push them. Typically found in warmer ocean regions of the world, they most often occur in large groups (the collective term for men-o-war is a navy), which means when they reach inshore waters together they get to be obnoxious en masse. They do appear on some shores regularly and seasonally. Australia has problems with them on its beaches, as do southern Africa, south-western Europe, and Caribbean islands. Their presence demands beach closures, as swimming within view of a live one can mean its tentacles, or severed tentacles of others nearby, are drifting through the water within reach. Being as poor yachtsmen as they are, unable to see or hear, having no control of their sail and rigging, they regularly get blown off the surface of the water by strong gusts and up onto beaches. Imagine a lopsided purple balloon with an electric-shock string flying merrily out of the water and splatting onto the patch of sandy beach likely to be trodden upon by bare feet throughout the day. Once stranded on land, the man-o-war can’t do much but sit there and look colourful . . . and sting.

Victims of this sting describe a never-before-experienced sort of pain; intense, deep, debilitating; something like a bad itch gone horribly wrong. The venom is a power cocktail of neurotoxins and histamines that is about 3/4 the strength of the venom of cobras. Often, immediate treatments administered include vinegar or urine, or packs of mud that are allowed to dry to draw out the poison. Vinegar provides short-term relief, but is not advised for use because it actually causes the remaining nematocysts to fire more strongly, and it is more suitable for jellyfish stings (and the man-o-war is not a jellyfish); mud packs are a great deal of work for not much return; and it has been suggested that the urine solution offers nothing more than a friend’s opportunity to have an embarrassing story to tell later.

The best immediate treatment is to physically remove the tentacles (with an object other than the fingers; stings can even occur through gloves), apply salt water, and later soak in water as hot as is safe to apply to skin, which denatures the venom. Stings rarely cause death or long-term discomfort, but allergic individuals are severely endangered by stings.

Despite all of this awful stinging, the man-o-war does actually have some friends, albeit not very good ones. The man-o-war fish is a bug-eyed fish that looks as though it is in a trance. Its skin is covered in a special mucous and possesses excellent manoeuvrability that prevents the nematocysts from firing, and it can hide safely in the drifting tentacles and nip parts of the man-o-war’s meals and tentacles. Sometimes it does get eaten by the man-o-war in turn. Several species of clown fish also associate with them. The Australian blanket octopus may act like a friend, but only until it rips off a clump of man-o-war tentacles with a sting-immune arm and carries them around with it, poking the cluster towards potential enemies.

The man-o-war has far more enemies than friends. The very Dr. Dolittle-sounding purple sea snail drifts around on the surface of the tropical ocean regions on a sail of its own, constructed from inflated bubbles of mucous attached to its body at the edge of its lavender or mauve shell. If the snail’s bubbles pop and it sinks, it will likely die of starvation — because it is on the surface where it finds its favourite food: man-o-wars. Despite the sting, the man-o-war is also a common food source for the blue sea swallow (a type of sea slug, which incorporates the unfired stinging cells into its own body tissues for defence), loggerhead and leatherback sea turtles, and the mola (ocean sunfish). Despite all these hungry predators (which have to eat loads of the things, since men-o-war are made of up to 95% water) they still come close to shore in droves. In late April 2010, they forced the closure of at least one beach in Providenciales.

Beach closures are only one of the reasons of why I declare Portuguese men-o-war as nature’s single most inconsiderate marine animal. Let’s face it: dangerous weapons and a complete lack of locomotion control, vision, and decision-making ability are a poor combination. If I had 150 feet of explosively venomous tentacles trailing behind me, I’d at least have the decency to follow the Australian carpet octopus’s example and use them carefully and selectively for defence. The man-o-war, though, just gets blown around by the wind, completely out of any sort of control, arbitrarily crashing into things and stinging whatever will receive its toxic harpoons. Researching these wretched little balloons-with-a-kick has allowed me to learn about their fascinating life histories, but it also sealed the deal on the declaration of them being the most inconsiderate and rude animal in the sea. Admire their beauty and eccentricity from a distance — they’re fascinating, just not very nice.

Sightings of men-o-war — and seeing one usually means more are coming — should be reported to the Department of Environment & Coastal Resources, so that their arrival can be monitored and proper precautions can be announced. Never try to touch a man-o-war, as they can sting even when dead, and through some materials.