A marine conservation group says fish catches in overfished European waters — stretching from the Arctic to the Black Sea — could increase by 57 percent if stocks were managed sustainably.

The Oceana environmental group says scientists believe catches of haddock, cod, herring and sardine in the Atlantic could increase by at least 300 percent.

Group spokeswoman Maria Cornax said Tuesday there was "no excuse" not to start fishing sustainably.

Oceana's research, which it billed as "the most comprehensive overview so far," was based on 397 stocks compared to around 150 monitored by the European Commission.

Oceana published its findings before next month's EU meeting to set next year's fishing limits in the North Sea. Oceana said 85 percent of stocks were now "in an unhealthy state."