Heatwave wipes out mussel crops
Santi Tomàs has sailed the waters of Badia del Fangar for decades, following in the footsteps of his father and grandfather. But this summer, he pulled up empty ropes from his raft, only a few algae clung to them. "Everything has died, what we should be harvesting now and what was growing for next year," said Tomàs, president of the Federation of Shellfish Producers of the Ebro Delta (FEPROMODEL). This season, just 2,500 tonnes of mussels were harvested across the Alfacs and Fangar bays, down from four million kilos in previous years. The harvest ended in July, according to FEPROMODEL.
Mussel mortality hits 500,000 kilos
Jordi Casanova, spokesperson for FEPROMODEL, said rising water temperatures caused the death of 500,000 kilos of commercial mussels after the harvest season, dealing a €1.2 million blow to the sector. "Above 26°C, mussels stop feeding; above 28°C, they die," Casanova explained, stressing that the danger lies not in short heat spikes but in sustained high temperatures lasting over ten days. This summer, water in Badia del Fangar exceeded 31°C as early as June. The prolonged heat killed natural larvae expected to be harvested in 2027.
The problem is not a heat spike, but the continuity of high temperatures for more than ten days.
Farmers face higher costs
With natural seeding failing three out of every four seasons, producers now rely on imported seed from Italy and Greece. The cost of juvenile mussels has more than doubled in four years, exceeding €1.20 per kilo. Farmers must also pay to dispose of dead mussels, 65 euros per tonne, as decomposing organic matter cannot be left in the sea. Earlier storms worsened losses: Storm Nils in February destroyed eight rafts and damaged 32 others at Fangar. EU FEMPA aid covered 60% of reconstruction costs, but producers absorbed all product losses.
Shift to oyster farming gains momentum
Facing an uncertain future, many shellfish farmers are turning to Pacific oysters, the only mollusc so far resilient to the region’s warming waters. "We’d grow some mussels before the intense heat arrives, then switch to oysters," proposed Tomàs. However, local demand for oysters remains low compared to mussels, and imported oysters from more prestigious regions dominate the market.
Climate change reshapes delta ecosystem
Susanna Abella, spokesperson for the Platform in Defence of the Ebre, warned that climate change is transforming the delta. Rising sea levels, increased salinity due to natural siltation, and stronger storms are disrupting the ecosystem. "Fish species that once spawned here no longer come," said veteran producer Ramon Carles. Native green crabs have been wiped out by invasive blue crabs, which now slip through protective nets. "Experts have warned about global warming for over 20 years, but we’ve done nothing to solve it," concluded Abella. "Only temporary fixes, calendars, declarations. We’re condemned, this has no solution." Still, producers hold onto hope, banking on the sector’s resilience and ability to adapt.
Primary sources: govern.cat. Reported by cronicaglobal.cat, Andrea Pacha Röper, diaridetarragona.com, ACN, Manipal Systems, diarimes.com, Guillem Costa.
