THE owners of a £1.5billion superport have backed a probe into a collapse in fish stocks in the Thames.

DP World, owner of the London Gateway port, has backed calls for an investigation into why sole catches have more than halved in two years.

Fishermen and Southend West MP David Amess, have blamed the decline on a channel being dug in the Thames so the world’s largest container ships can reach the port, off the Manorway, in Stanford-le- Hope, but no link has been established.

DP World, which compensates fishermen for the impact on their livelihoods, points to other factors, including new fishing techniques and seasonal fluctuations as being the probable cause.

Other public bodies responsible for the marine environment are also investigating.

Xavier Woodward, communications manager for DP World, said: “We fully support the investigation into fish stocks.

“Our maritime work in the Thames has been planned and carried out with the full support of Government environmental experts and is highly regulated.

“London Gateway has funded marine monitoring carried out by independent experts since 2002 and has shared all collected data with the Ecological Advisory Group, which includes the Environment Agency, Natural England, the Port of London Authority and the Kent and Essex Inshore Fisheries and Conservation Authority.

“The group assesses the work and the results from information collected and validates it. If any further checks are needed this also then takes place to ensure all environmental protection bodies are fully satisfied.

“We will continue to be fully open and transparent with all parties.”

The amount of sole caught by Leigh fishermen has fallen from 18 tonnes in 2011, the year after the contractors began removing 27 million cubic m of material from the seabed, to eight tonnes last year.

The Centre for Environment, Fisheries and Aquaculture Science, which advises the Government on managing fish stocks, called for seasonal restrictions on dredging at a public inquiry into the port plan, but the independent inspector rejected the suggestion.

Dredging was due to finish this year, but further “maintenance dredging” will now take place.

John Lamb, chairman of Kent and Essex Inshore Fisheries and Conservation Authority and chairman of the Association of Inshore Fisheries and Conservation Authorities, said: “We know there has been a drop in the fish stocks, but what has caused it? We can’t deal with it without understanding the cause.

“We knew when the DP World port was being built, when it went to a public inquiry, there was a sole nursery nearby.

“The inquiry said that would be damaged in the short term, but the scientific experts said when the dredging was finished it would re-establish.

“We were told the dredging would be ‘self-scouring’, meaning the tide would move and stop earth building up in the channel. Now we have got to watch if there will need to be maintenance dredging.”