Beach-goers advised to avoid Portuguese man-of-war

Captain Beau Begin spotted man-of-war floating in Vineyard Sound on Sunday.
Photo by Beau Begin

Captain Beau Begin spotted man-of-war floating in Vineyard Sound on Sunday.

It is not unusual for Vineyarders to report sighting the balloon-shaped sail of Portuguese man-of-wars in the summer months. But sightings in early June are unusual.

On Sunday, captain Beau Begin emailed The Times to report sighting over a dozen of the stinging creatures in Vineyard Sound floating amid “a massive debris/weedline” generated by the passage of tropical storm Andrea on Friday.

“I just wanted to warn people who may be swimming to be careful of them,” he said.

This week, Chris Kennedy, The Trustees of Reservations Martha’s Vineyard superintendent, told The Times he had received reports of man-of-wars washing up on Norton Point beach in Katama and Long Point Beach in West Tisbury.

Mr. Kennedy said The Trustees would post signs cautioning people not to touch the creatures. “It happens every year,” Mr. Kennedy said, noting that this was earlier than usual. “Avoid them and you will be safe.”

Aquinnah town administrator Adam Wilson Wednesday said a woman reported seeing numbers of man-of-wars on Philbin Beach, but he could not confirm the sighting.

The recent passage of a tropical storm and the animals’ primitive propulsion system likely transported the man-of-wars to Island beaches, where its appearance is something of a rarity.

The beauty of a man-of-war and its long streaming tentacles in the water hides a venomous sting. The animal’s tentacles, which can grow to be 40 feet long, are used to secure small fish for food and can inflict nasty welts on any swimmer unlucky enough to encounter one in the water.

The tentacles contain thousands of stinging cells, each of which is essentially a tiny microscopic coiled up harpoon.

Experts say the best advice is to steer clear of Portuguese man-of-wars in the water and on the beach.