Dangerous jellyfish, including man-of-war, off New Jersey

Jellyfish have long been a stinging fact of life at the Jersey shore, but lately some dangerous species have been making their way to the area.

Lifeguards in Harvey Cedars on Long Beach Island discovered a Portuguese man-of-war on Sunday. The National Oceanographic and Atmospheric Administration says the species is highly toxic and packs "an intense sting."

The painful sting can in some instances can be life threatening. The man-of-war also has tentacles that can grow as long as 30 feet, and is usually found in warmer waters.

Box jellyfish also were found in Ocean County last fall, laden with tiny, painful poison darts.

But experts don't think New Jersey is in for an invasion of the more dangerous jellies. Rather, they say, these are a few isolated instances of warm-water creatures catching a ride north on the Gulf Stream, and winding up on shore due to wind or tidal patterns, something that is not all that unusual.

"Nobody is saying this is a new trend that we're going to be seeing more of," said Tim Dillingham, executive director of the American Littoral Society. "They show up periodically, get caught in the Gulf Stream, spin off and wind up here."

Montclair State University professor Paul Bologna agrees both species probably rode Gulf Stream currents up from Florida, where they are common.

The Portuguese man-of-war is a floating colony of polyps with a pink or purple gas-filled float and numerous, long tentacles. Although their stings are rarely fatal, "the Portuguese man-of-war is highly toxic; contact with its tentacles will result in a painful, intense sting, welting, and blistering. People in the water must be aware that man-of-war tentacles can drag for up to 30 feet behind the animal," NOAA said.

Box jellyfish, named for their body shape, have tentacles covered in nematocysts, which are tiny darts loaded with poison. The Australian species is the most lethal and one of a small amount of species whose sting can actually kill people. The ones spotted in Ocean County and in the Manasquan River last year were a less-dangerous Atlantic species.

Far more troublesome to the local marine environment, scientists agree, is the increasing number of the most common stinging jellyfish, known as sea nettles, particularly in Barnegat Bay. Warmer water, reduced oxygen content and pollution runoff have all combined to help increase the numbers of sea nettles in area waterways where swimmers are increasingly being stung.

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