Morrisons in line-caught tuna effort

The retailer stated that it has forged relationships with fishermen in the region who have implemented sustainable ways of working, ensuring that fish will be replenished.

Fish buyer at Morrisons Matthew Bailey noted that the fishermen are greatly experienced in their field and that boats used are independently owned.

Development director at The Sea Fish Industry Authority Jon Harman added that efforts have been made to ensure that sustainable tactics are used.

He said: "Fish stocks are controlled by quota set under management plans guided by scientists and the Cornish Fishermen have worked with industry experts to ensure that tuna found in the Bay of Biscay is fished within quota and responsibly."

Rates of harvest are restricted because only one fisherman is allowed top trawl the waters at a single time, the supermarket stated.

Moreover, Morrisons said, if there are hundreds of the type of fish close to a boat, they will not all be caught as there are fewer than 14 lines.