Beachgoers are being warned to keep an eye out while enjoying the weather as Portuguese man o’ war have made an unwelcome arrival.

The bluish, ballon-like organisms, often mistaken for jellyfish, have been washing up on the island’s beaches in increased numbers this week, with one member of the public counting 84 on Horseshoe Bay on Thursday afternoon.

A spokeswoman for the Ministry of the Environment called on the public to take extreme care while in or near the ocean, noting the organism’s painful sting.

“Portuguese man o’ war can be identified by their bluish, gas-filled float on top of the water,” the spokeswoman said. “Their tentacles drift below the surface of the water and often they are difficult to see. These tentacles cause extremely painful stings. Stay away and do not touch these jellyfish even if they are on land as the tentacles can still be very venomous.”

Those who do suffer stings are advised to carefully remove tentacles without using bare hands to prevent further stings.The affected area should then be treated with seawater to flush away any remaining tentacles.

To treat the pain, hot packs or hot water should be used for up to 30 minutes, followed by burn ointment and a light dressing. Pain relief medication can also be used.

March to June are considered the peak month for Portuguese man o’ war stings on the island, with the animals often being washed ashore after a storm or period of strong winds. While often referred to as jellyfish, man o’ war are actually siphonophore — a floating colony of specialised individual animals called zooids or polyps. Each of these organisms are bound together so they require each other for survival.

The organisms usually float on the open ocean, using the venom in their dangling tentacles to paralyse their prey.

While individual stings can result in red welts on the skin that linger for up to three days and pain for several hours, larger numbers of stings can result in more serious issues.