The last thing you want to see when you are on vacation is a jellyfish, as even the sight of one can make you worried about heading into the water. Researchers now want to help beachgoers with an app that predicts jellyfish movements.

"This year is a jellyfish year," says Jamileh Javidpour, professor at Syddansk University in Denmark.

They've come earlier than expected to Baltic Sea beaches this summer – and not just harmless ones like rib and ear jellyfish, said Javidpour, working on a new project to track waves of jellyfish.

With its "GoJelly" project, the European Union is conducting research on the distribution and use of jellyfish in which the Syddansk University and the Universities of Kiel and Hamburg in Germany are participating.

Using the smartphone app Jelly Spotter, users can send the researchers pictures of jellyfish on coasts along the Baltic Sea. In doing so, they help to learn more information about the jellyfish population in the western Baltic Sea.

"The app helps us gain access to coastal regions in the Baltic Sea that we ourselves lack access to," said Javidpour. "The more users, the better," she added.

In addition, the researchers are also relying on drones.

The jellyfish forecast

With the help of the app, the researchers now want to develop models of how jellyfish occurrences can be predicted in the future. Ideally, a corresponding function could be added to the app as early as summer 2022, Javidpour said.

While the app initially is set to predict waves of jellyfish for people visiting northern Germany's beaches, the research is promising for beachgoers everywhere where stinging jellyfish are known to appear.

The occurrence of jellyfish changes from year to year explained Javidpour, a marine biologist who has been monitoring the jellyfish population at the German coastal city of Kiel for 17 years. The mild winter and the comparatively cold spring caused a rise in numbers this year, she said.

"Jellyfish need a temperature shock. When they are in shock, they produce many more medusae," she said. These drift to areas where conditions are better. That's why beachgoers will often find many more animals in one area than they might 100 meters away.

What do you do if you've been stung by a jellyfish?

If you get stung by a jellyfish, the best thing you can do is wash the area with diluted vinegar.

Beaches where jellyfish stings are common will often have emergency bottles of diluted vinegar ready for such instances. If you can't find one, seawater will also help, pharmacists advise.

Freshwater, on the other hand, will only make the nematocysts, the jellyfish's venomous stingers, open up, so you should avoid having a shower or rinsing the sting with tap water.

Another good way to lessen the stinging is by spraying on shaving foam. You should feel better if you let it dry on the affected area of the skin and then scrape it off with a credit card.

Cooling down the area should give some relief, and you can take anti-inflammatory medication to ease the pain caused by the sting. If the sting stretches over a large area or if you experience an allergic reaction to the jellyfish, you should see a doctor.