Since mid-June dozens of Portuguese man-of-wars have been sighted in the waters and on the beaches of New Jersey. Warm waters, carried in from the Gulf Stream are thought to be responsible for the influx of the, potentially dangerous, animals. The man-of-war typically inhabits tropical and semi-tropical waters around the globe.
“It probably came up with the Gulf Stream and then we had a little bit of a north swell move in. So that [critter] might have drifted in,” John Tiedemann, director of the Marine and Environmental Biology Policy Program at Monmouth University in New Jersey, told Live Science.
Frequently mistaken for jellyfish, the Portuguese man-of-war is actually not an animal but a colony of organisms working together as if they were a single creature. The colony, called a siphonophore is made of four separate polyps which perform separate functions.
The first part is a gas filled bladder which sits above the water and is described by National Geographic as resembling “an old warship at full sail”. The second part of the siphonophore is the tentacles which extend an average of 30 feet below the water, but can reach up to 165 feet.
It is these tentacles which make up the dangerous part of a man-of-war. They are covered with venom filled nematocysts which are used to immobilize and capture prey. The venom is rarely fatal for humans but can be extremely painful. It is worth noting that, contrary to popular myth, peeing on a man-of-war or other jellyfish sting can actually make it worse.
Anyone who experiences an extreme reaction or who is normally sensitive to animal venom, such as bee or wasp stings, should seek medical attention according to Live Science. It is also important to avoid touching a man-of-war, even if it is dead. Stinging is not an active decision for the creatures but something that happens when its tentacles are touched. This means that it is no less dangerous after death.
The remaining two polyps in a man-of-war handle digestion and re-production.
In their traditional, warm water homes, man-of-wars can appear in groups of 1,000 or more. The reach of their tentacles can make swimming anywhere near one of these groups a risky proposition. There is no evidence at this point, however, that they exist in such numbers off the coast of New Jersey.
While climate change and a warming ocean could allow man-of-wars to expand their range, the New Jersey sightings appear to be an anomaly for the time being.
“Our land happens to be in the direction of the wind and waves. And the water is warm, which is keeping them alive. They probably have enough food to sustain themselves,” Surf City councilman Peter Hartney told NJ.com.
