Birds Eye is hoping to hook people on a new type of fish finger, in an effort to persuade them to eat less cod.
Last year, Birds Eye caught about 17,000 tonnes of cod
It hopes the launch of a new fish finger - made of Alaskan pollock from a sustainable fishery - will help cut its cod catch by 4,000 tonnes a year.
Cod quotas have been reduced amid fears the species could be wiped out in some areas, such as the North Sea.
The WWF and Marine Stewardship Council (MSC), which certifies sustainable fisheries, both welcomed the news.
"The North Sea cod population is estimated to have been well below 70,000 tonnes for the last 10 years," said Tom Pickerell, Fisheries Policy Officer for WWF.
"If the stock does not rebuild there is a danger it could become commercially extinct," he warned.