A survey of catches at European ports has found that fishermen did not catch a single cod over the age of 13 last year.
The findings raise concerns for future stocks of cod, which become more fertile as they age. The fish can live as long as 25 years and grow to 6ft.
Researchers warned a lower life expectancy meant a lower birth rate and a faster decline.
Callum Roberts, professor of marine biology at York University, told the Sunday Times that intense industrial fishing meant that few fish survived beyond the age of four, when they reach sexual maturity.
“This means that there are fewer eggs and larvae to perpetuate future generations,” he said.