Abnormally high sea temperatures wreak havoc on Spanish mussel crop

Tarragona, Spain, Aug 24 (EFE).- Unusually high water temperatures of the Mediterranean Sea driven by a sequence of heat waves across southern Europe have killed off over 150,000 kilos of seasonal mussels and an estimated one million juvenile mussels due for harvest next year in Spain’s northeastern Ebro Delta region.

The massive loss of juvenile mussels means farmers will have to source their mussels from Italy and Greece next year, increasing the price of the product in Spain, the manager of the region’s producers, Gerard Bonet, told Efe.

Mussel farmers in the Ebro Delta, located in Catalonia, have been faced with the crisis for weeks, collecting dead material and empty mussel shells from what used to be a plentiful area of the Mediterranean Sea.

“The effects of climate change have been felt for years, although the summer of 2022 has marked a before and after,” Bonet said, adding that seawater temperatures reached over 28C (82.4F) in July and up to 30C in August.

While the industry has been adapting to the changing conditions by shortening the cultivating season and producing less, it has not been easy.

“Mussels can only be removed from the water and sold if they are full of meat, they have a short life span,” he explained.

Every year, between 3 and 3.5 million kilos of mussels are farmed in the Ebro Delta. Bonet estimates the losses this year have cost the sector up to 1.5 million euros ($1.48 million dollars).

Mussels are key to the Delta ecosystem, the largest wetland on the Mediterranean coastline, because they filter the water by absorbing nutrients and serve as food source for numerous species of aquatic birds.

“The problem is not reaching high temperatures for a day or two, but when they are maintained for so long,” Bonet said.

Since May this year, Spain has been faced with a series of intense heat waves and lack of rainfall that has resulted in droughts and severe wildfires in many parts of the country.

In mid-August, sea temperatures reached a record high, 6C above the average temperature, according to the European monitoring satellite Copernicus. EFE

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