Else Beekman
With the arrival of summer and the heat, the so-called fried egg jellyfish (Cotylorhiza tuberculata) have reappeared in large numbers on several Spanish beaches. According to the latest report from the Murcia government, numerous young jellyfish of this species have been detected in the Mar Menor.
At almost all seven sampling points, large quantities were reported, ranging from 50 to 500. At one point, an estimate of 1,000 specimens was made. Last year, there was also a birth explosion of these ‘huevo frito’ jellyfish. They range in size from one millimetre at birth to approximately 30 centimetres after one to one and a half months when they become sexually mature. They usually live for two to six months. This makes them more common during the summer season when tourism on the Spanish coasts is at its peak.
An explosive birth peak in Mar Menor
The report warns of the intense birth peak of these jellyfish in the Mar Menor. Millions of fried egg jellyfish are in the early life stages, known as ephyrae and metaephyrae. The report explains that, like last year, the phenomenon is “very prolonged” and that “the strongest birth peak is occurring these days.” The report raises the question of when the jellyfish’s reproductive process will end and thus their birth. Researchers are closely monitoring the evolution of the already present specimens since the “levels of zooplankton are very low.” This could lead to the death of a large part of the population or very slow growth, extending their life cycle, as was the case last year.
The next sampling will evaluate the continuity of the fried egg jellyfish reproduction over time. However, the “large number of jellyfish will make sampling difficult as they clog the trawler’s net,” the report concludes.
After the rains
Fieldwork in the Mar Menor was carried out on Thursday, May 13, a day after 100 million litres of water entered the lagoon due to “the heavy rainfall of the previous day.” Although the rainfall did not alter the conclusions of the fieldwork, a minor birth of other jellyfish such as P. punctata (the Australian spotted jellyfish) and particularly R. pulmo (the sea walnut) was also detected. “It is likely that, as last year, the populations of these two jellyfish species will be overshadowed by the high concentrations of fried egg jellyfish.” However, many ephyrae of the sea walnut were also detected. Additionally, the report concludes a large presence of large, isolated adult sea walnuts throughout the Mar Menor.
What are fried egg jellyfish?
Fried egg jellyfish get their name from their appearance. They are yellow with an orange protrusion in the middle, resembling a fried egg. They can grow up to 30 centimetres and have a lifespan of two to six months. Their increased presence is attributed to human activities, climate change, and meteorological conditions.
What to do in case of a jellyfish sting
Although the sting of a fried egg jellyfish can be annoying and irritating, it is not toxic. However, it can cause a burning sensation on the skin. The recommendations are as follows:
- Rinse the affected area with seawater, not fresh water.
- Rub the sting with onion, vinegar, water with baking soda, or even urine to relieve the pain.
- Treat the area with alcohol two to three times a day for three days.
What is Mar Menor?
Mar Menor is Europe’s largest coastal saltwater lagoon, located on the southeastern coast of Spain, adjacent to the Mediterranean Sea. Once known as ‘the crystal sea’ for its clear water, the lagoon is now often referred to as ‘green soup’ due to severe pollution from pesticides and sewage. This polluted water comes from the nearby Campo de Cartagena, the largest agricultural area in the region. The pollution has led to large-scale fish deaths and ecological collapses. Although there has been some improvement, drastic action is needed to restore the damage. Tourism in the region largely depends on Mar Menor, but the high visitor numbers and intensive agriculture put excessive pressure on the fragile ecosystem.
Also read: Swimming in Spain without jellyfish? Do the check