Why are there no jellyfish on Granada's beaches this year?

The number of jellyfish stings reported on Granada province's Costa Tropical has gone down by 90 per cent this year compared with summer 2023.

The yellow flag and jellyfish signal to warn beachgoers hasn't been raised so far this summer and fewer than 10 stings have been treated at each lifeguard post. In Almuñécar-La Herradura, there have been only 60 lifeguard interventions in total compared to 251 last year. However, the summer of 2018 holds the record when more than 3,000 stings were treated.

In Salobreña, the Red Cross has participated in 61 actions compared to the 279 in which it collaborated in the same period last year. In 2023, the first aid services acted in 231 jellyfish stings compared to seven this summer.

According to Julio de La Rosa, director of the Aula del Mar, the presence or absence of jellyfish is due to several factors. The main one is the marine currents. The winds displace the superficial layer of the water (due to the coriolis effect and the Eckman's spiral) that drags the jellyfish and also remains of rubbish to the shores. So far, currents have not been favourable to their proliferation or reproduction this year, despite some warm spells.

The species most frequently observed on the coast is the 'Pelagia noctiluca', the common jellyfish, a small, pink creature with eight tentacles that it uses as a net to capture its food. The 'giant' jellyfish, the species 'Rhizostoma Luteum', a rare jellyfish in the Mediterranean that can weigh up to 40 kilos has not been spotted this year either.

It first appeared on the Spanish coasts in 2012 and even then there was no photographic evidence to confirm its presence. The first sightings of this species occurred in Murcia, Almeria and Granada. It is translucent white with purple tones and it has long tentacles that are grey and the ends. They can reach a length of between two and three metres.

Unlike other jellyfish, they have numerous mouths and feed on plankton. Rhizostoma luteum has a special feature compared to other jellyfish: it can live with other organisms. There are fish that live among its tentacles or in its umbrella-like body. Its tentacles sting, but they are not as painful as some smaller species of jellyfish.