The economy of Carloforte was influenced by the presence of the tunny-canneries of Porto Paglia, Cala Vinagra, Portoscuso and Isola Piana. The tunny-canneries in Porto Paglia worked till 1973 when the society which managed it closed down and so the plant went to rack and ruin. The tunny-cannery in Portoscuso worked till 1976. Later on it became the plant where the tunnies fished in the "tonnare" of Isola Piana were processed (cuore, musciame, bottarga). The latter is now a residence compound. Nowadays everyone can watch the "mattanza" in the waters of the "tonnara" of Portoscuso and Isola Piana run by co-operative societies.