Portuguese Man-O-War

Portuguese Man-O-War
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How to avoid these stinging creatures and what to do if you get stung.

• General: DIY / How-To • General: Educational • General: Guide

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The Portuguese Man-O-War, or Blue Bottles as they're called, are a jellyfish-like sea animal that is known as a neuston, or an aquatic animal that lives along the surface layer of the ocean. In most cases, these creatures live far out in the ocean and away from beaches but since they go with the flow (literally) they can drift towards beaches and become a hazard to human beachgoers.

Portuguese Man-O-War Details

Most people think the Portuguese Man-O-War are jellyfish, which isn't true. Though they are related to the jellyfish family they are actually part of the feathery hydroid colonies that you might see growing on pier pilings in the ocean.

Within a colony of the animals, one of them gets modified into a pneumatophore, which is basically a gas filled float. The others will attach themselves to that one animal with the floatation device and hang on. The float acts like a windsail and so the winds and ocean currents dictate where the colony goes.

Long, trailing tentacles (that can reach well over 30 feet long!) contain stinging cells that can inject a barbed thread and paralyzing toxin into prey they find along their journey. When a small fish is caught, the tentacles transfer the prey to the everyone on the floating party barge and the nutrients are shared through a common gut that connects them all together. Even more amazing is that the members all communicate using a network of nerve fibers. Amazing nature!

So why are they called Portuguese Man-O-War? To early explorers, that gas filled bubble that keeps the colony floating resembled the war helmets worn by Portuguese soldiers. Neat, right? These creatures have several Hawaiian names such as 'ili mane'o, palalia, pa'imalau, and pololia.

How To Avoid Portuguese Man-O-War

If you see a man-o-war you'll want to stay far away from it as it can be difficult to see exactly where those sting tentacles are. In fact, it can often be difficult to see them at all in the water until you're very close because they blend into the water. Their translucent blue color makes them difficult to see against a blue ocean background.

Just like any sea creature, a man-o-war can appear at pretty much any beach at any time. When they do appear, they can sting you in the water or even when they wash up on the beach. They can still sting even days after being beached. Disposing of them would best be done with a long stick if needed.

Here in Hawaii they do tend to make appearances at some of our beaches. They appear most frequently on the windward (northeast) sides of all of the Hawaiian Islands. Since our tradewinds blow from the northeast and to the southwest it's easy to see how these creatures, with their sails, would end up on the northeast shores.

So, if you're visiting a windward side beach you should talk with lifeguards before entering the water. They're your best bet for current conditions and hazards. If there aren't any lifeguards around I would try to find some locals and ask if they're seeing the creatures. If you still plan to get in the water go slow and really look around on the beach first, if you see them washed up on the sand don't go in the water. In the water, the animals often look like plastic bags or plastic wrap, much like Hawaii Box Jellyfish do. If you ever see one in the water, get out right away as there are likely many more nearby.

What To Do If Stung By A Portuguese Man-O-War

If you get stung by a Portuguese Man-O-War in Hawaii you'll know it. For some, the pain can be fairly intense depending on how many stings got you and where on your body it happened. A red rash and/or welts will likely appear in the area that was stung.

If a lifeguard is a the beach you're at then go to them right away. They can help treat it and even get medical help if you're having an allergic reaction to the venom.

The next step is the remove the tentacles with tweezers, chopsticks, or something flat like a fork or knife and then rinse the sting with salt water to remove any nematocysts. Some say that rinsing with fresh water is fine, others say fresh water will make it worse. It's said that using KY Jelly can help as it won't irritate the man-o-war, but if you have KY Jelly with you on the beach, well, maybe you need to read up on your Beach Etiquette.

We're not doctors and this is not medical advice, but we've heard that for minor swelling and itching, Benadryl may help. Don't bother having anyone pee on you either, that won't help unless you're going for the "laughter is the best medicine" approach to healing. White vinegar sprayed on the wound may help neutralize the venom.

Try applying ice to help with the pain. If the pain is severe or you believe you may be having an allergic reaction find medical help right away. For emergency assistance dial 911.