Consumers eat more seafood than ever before and increase the pressure on already strained fish stocks. We urgently have to take action to secure seafood supplies and meet future demands.

Retailers can play a decisive role in leading fisheries on to a sustainable path since their purchasing power gives them a strong voice within the seafood industry.

The move by several retailers towards sustainable fish sourcing deserves praise. Already there is evidence that these initiatives urge fisheries to improve their conservation practices. We have seen sourcing policies that highlight environmental considerations and favour seafood sources that are certified against the Marine Stewardship Council's environmental standard.

However, some supermarkets still sell fish from endangered stocks or from species that are known to be overfished. Sensitised consumers are looking for alternatives, but struggling to find them.

The media and confused shoppers often ask us why there is still cod available at supermarkets if there is such a problem in the North Sea. We all understand the British dedication to cod and haddock, but current supplies, even taking into account the other seas that supply cod, cannot support the rising demand.

Instead of continuously increasing prices and offering no alternative, my suggestion is for retailers to introduce pollock, hoki, hake or saithe and tell customers why on the pack. Support it with a strong sustainability message and recipes to help the nervous consumer.

Better yet, put it on promotion. Develop in-store materials, organise cooking demonstrations, offer a competition and place ads.

Sainsbury shows a great example of how to introduce new, unfamiliar species to the market. Its Just Cook range offers pre-pack fish in sauce and is regularly sold at 2 for £5, which encourages shoppers to try a new species without spending a lot. It is ready to cook so the fear of preparing an unfamiliar fish is taken away. The MSC eco-label on retail packaging makes it even easier for consumers to identify fish from sustainable sources.

In the past we were told that there was not enough sustainable MSC-certified fish to meet consumer demand. With 32% of the world's prime whitefish now engaged in the MSC programme, this excuse is quickly disappearing.

The market is ready for a turnaround. Seize the opportunity and talk about your sustainable policies.