Media playback is unsupported on your device

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.