Several instances of a red or orange discolouration of sea water along beaches in Málaga and Granada have been reported in recent weeks. However, scientists say this is a completely natural phenomenon and poses no danger.

Nerja was one of the resorts where the water turned red in places, thanks to the spawning season for certain sea creatures.

Here and along the coast of Granada, hundreds of other creatures appeared on beaches but experts at the Aula del Mar in Málaga said they should not be confused with jellyfish, to which they are not related. The harmless salp

has the appearance of a chain and moves by contracting and pumping water through its gelatinous body making it is one of the most efficient examples of jet propulsion in the animal kingdom.

Experts say salps – sometimes known as Venus Belts – absorb large quantities of carbon dioxide but usually live in cold water and have been affected by climate change. They should be left alone to avoid creating “damaging effects on the balance of nature.”

Meanwhile, a dozen boats have been contracted to keep the water clean for bathers off the coast of the Axarquía this summer. The fleet is costing €270,000 to keep the sea clear of rubbish off the coasts of Nerja, Torrox, Algarrobo and Vélez-Málaga, while Rincón de la Victoria has its own cleaning boats.

Last year, more than 47,000 kilos of organic matter and about 865 cubic meters of oil were collected and treated, plus other 39,000 kilos of inorganic waste, mostly plastics, cans, branches and wood. The boats, supplied by Servimar Axarquía, are also equipped to deal with jellyfish and will continue working until September 15.