Since May 2025, local authorities in Cádiz have removed 1,200 tonnes of this algae from La Caleta, the city's most popular beach, including a maximum of 78 tonnes in a single day. "We are completely overwhelmed. This is an environmental catastrophe," declared José Carlos Teruel, head of beaches for the Cadiz city council, who added that every time a westerly wind blows, they know they are in for another wave of seaweed.
The species, 'Rugulopteryx okamurae', which is believed to have arrived in the ballast tanks of ships passing through the Suez Canal and unloading in the Mediterranean, has colonised the Strait of Gibraltar, much of the southern Spanish coast, the Canary Islands, the Azores and, further north, the Cantabrian Sea and the Basque Country in little more than a decade. It was first detected ten years ago in Ceuta by a researcher from the University of Malaga.
