Portuguese Man O’ War are found in Florida’s coastal waters, particularly along the Atlantic and Gulf Coasts, carried by winds and currents. While they resemble jellyfish, they are biologically distinct colonial organisms.
Where Man O’ War Are Found and How They Look
Portuguese Man O’ War are common along Florida’s Atlantic coast, from Jacksonville to Miami, and occasionally on the Gulf Coast. Their presence on beaches is often influenced by strong onshore winds, especially during winter (November through April). These creatures do not swim independently; instead, wind and ocean currents propel them, leading to large numbers washing ashore.
Their distinctive appearance makes them recognizable. A Portuguese Man O’ War features a gas-filled float, known as a pneumatophore, which can rise up to six inches above the water. This float often displays iridescent hues of blue, violet, or pink, and has a crest that functions like a sail, catching the wind. Dangling beneath this float are numerous long tentacles, typically extending around 30 feet, though some can stretch over 100 feet. These tentacles are equipped with microscopic stinging cells called nematocysts, which deliver a potent venom. Even when washed ashore, these organisms can still deliver a painful sting, as their venom remains active for hours or even days.
Are They Jellyfish?
Despite their common name, Portuguese Man O’ War are not true jellyfish. They belong to a group of marine animals called siphonophores, which are colonial organisms. This means each Portuguese Man O’ War is a colony made up of many specialized individual animals, called zooids, that work together as a single unit.
Each type of zooid within the colony performs a specific function, contributing to the survival of the whole. For instance, one zooid forms the gas-filled float, while others are specialized for feeding, defense, or reproduction. These individual zooids cannot survive independently; their survival depends entirely on their collective function within the colony. This cooperative structure distinguishes the Portuguese Man O’ War from solitary organisms like true jellyfish.
Avoiding Stings and What To Do If Stung
Avoiding contact with Portuguese Man O’ War is the most effective way to prevent stings. Beachgoers should remain vigilant, especially during strong onshore winds when these organisms are more likely to be present. Heeding warnings from lifeguards, often indicated by purple flags, is advisable. Avoid swimming in areas where they are sighted and never touch specimens washed ashore, as their stinging cells can remain active and potent for an extended period.
If a sting occurs, move out of the water to a safe location. Carefully remove any visible tentacles from the skin using tweezers, a gloved hand, or the edge of a credit card; avoid using bare hands or rubbing the area, as this can cause more stinging cells to discharge. Rinse the affected area with saltwater, not fresh water, as fresh water can trigger remaining stinging cells to release more venom.
Rinsing the sting with vinegar can be helpful to deactivate nematocysts before applying heat. After rinsing, immerse the affected area in hot water, ideally between 104°F to 113°F (40°C to 45°C), for 20 to 45 minutes. This heat helps to inactivate the venom and reduce pain. Avoid applying ice packs, alcohol, or urine, as these methods can worsen the sting. Seek medical attention if the pain is severe, the wound worsens, or if symptoms such as difficulty breathing, chest tightness, widespread swelling, dizziness, or nausea occur.