Swimmers and surfers have been the first to sound the warning that there are blooms of jellyfish very close to the Costa del Sol shores and some specimens have also been found washed up on the beaches.
Despite wearing wetsuits, fins and gloves, several surfers have already suffered from stings.
The warning comes at the start of the Easter holiday when higher temperatures and clearer skies will encourage many people to visit the beaches.
Marine biologist Jesús Bellido, at Malaga’s Aula del Mar acknowledges that they have located specimens along much of the Costa del Sol, from Nerja to Mijas.
The most common jellyfish and the one forming the largest blooms is the stinging pelagia noctiluca. It is usually small, so it is difficult to see it in the water.
Some specimens of the much larger Portuguese Man o’ War, that may look like a bloated jellyfish, but is actually a siphonophore, have also been spotted. Its sting causes severe pain and sometimes breathing problems.
The biologist explains, "We are receiving notices from all the points where there are people walking, swimming or surfing, it is widespread."
The good news is that the Malaga Meteorological Centre is forecasting a change in wind direction that tends to drive the jellyfish out to sea, although bathers will still have to be vigilant.