We inform visitors about the potential appearance of jellyfish in Telašćica Nature Park aquatorium.

In the period from July 17 to August 22, Center for Marine Research of Ruđer Bošković Institute received 59 reports of sightings of nine species of gelatinous plankton and several reports of jellyfish stings. Among the observed species, two can be dangerous for humans and can cause (severe) stings. These species were also the most frequently observed. Those are mauve stinger Pelagia noctiluca and cigar jelly Olindias muelleri. Mauve stinger (most often in clusters) was observed along the coasts of Vis, Korčula, Lastovo, Lastovnjak, Biševo, Silba, Zadar, Molat, Iž, Ist, Premuda and Lokrum. Single individuals of the species Olindias muelleri were observed in Premantura, Rovinj, Nin, Zadar, Korčula, Ugljan, Lošinj, and clusters of several individuals were observed along the coast around Pirovac and Funtana.

Mauve stinger is pink or purple to orange-brown with dots of a darker color. Through the transparent bell you can see the gonads in the shape of a four-leaf clover of an intense pink or brown color. It is relatively small, with the diameter of the bell usually less than 10 cm, in the Adriatic most often from 5 to 6 cm. There are 8 tentacles on the edge of the bell, which when fully extended can be up to 2 m long. That’s why it often happens that swimmers don’t notice jellyfish that burned them. The mauve stinger is considered the most dangerous jellyfish in the Mediterranean Sea. Sting symptoms most often appear locally at the location of contact. These are mostly skin reactions in the form of redness, pain, itching, a strong burning sensation and the appearance of blisters. Complications occur less often, i.e. stronger allergic reactions. Olindias muelleri stings are common in the Mediterranean, but milder than those of mauve stinger, and the symptoms usually disappear after a few hours. Jellyfish can be recognized by a transparent bell with a diameter of 4 to 6 cm with 4 radial channels with yellow-orange or reddish gonads along the entire length. On the edge of the bell there are 2 sets of tentacles, reddish or yellow primary tentacles with sticky pads and darker secondary tentacles. Unlike the mauve stinger, which survives its entire life cycle in the water column, Olindias muelleri stays on sea grass or macroalgae during the day, and after sunset they become active and swim in the water column. That is why we see them in shallow closed bays with dense meadows on the seabed, most often in the warmer part of the year.

There is no protection against jellyfish stings. We advise you not to enter the sea when mauve stingers are visible. If you do enter the sea, protect yourself by a lycra or neoprene suit and keep your face above the water. In case of contact, it is necessary to wash the sting site with sea water (not fresh) and gently scrape off the remaining jellyfish tissue from the skin. Cool the sting site with ice (but not directly on the skin) and apply products that cool and soothe the skin. In case of more severe symptoms and complications, it is necessary to seek medical help.

The mauve stinger is a holoplanktonic species, which means that it survives its entire life cycle in the water column. It swims quickly and actively, but its appearance, as is characteristic of all planktonic organisms, depends mostly on sea currents, tides and weather conditions. Therefore, it is very difficult to predict the exact locations and times of occurrence. Distribution maps of Olindias muelleri jellyfish and mauve stinger are available on the link: https://www.facebook.com/CIMrovinj/posts/pfbid02wmum8YwXP5hbxZLKrMvLi7533C4mtYqNoVGYeoeWdkYJZB8ycSZiSh9HHZQdH1Lnl?locale=hr_HR