Mackerel overfishing raises sustainability concerns
22 January 2013 Last updated at 18:46 GMT
The Marine Conservation Society (MCS) has downgraded mackerel from its list of fish suitable to eat.
The society says that international arguments about quotas mean it is no longer a sustainable choice.
It says that mackerel should now be eaten only occasionally and consumers should instead eat herrings or sardines.
Ed Thomas reports.