Fishermen's fears over dumping a million cubic metres of dredgings from river Tees into North Sea

Fishers and some researchers believe the release of a toxic chemical called pyridine from dredging on the river last October was to blame for a mass die off of crustaceans on a stretch from Seaton Carew to Whitby.

Defra concluded the most likely cause was an algal bloom.

Fishermen, however, say problems have persisted with crabs absent from inshore waters and dead or dying lobsters among recent landings.

South Tees Development Corporation, which is carrying out dredging for the quay, which will service the offshore wind sector, landfilled 125,000 m3 of sediment, after Mayor Ben Houchen pledged that "not a single gram” would be dumped in the river or out to sea.

However another round of dredging starting in the New Year will see 1m m3 being disposed of around 10 miles offshore.

Andrew Beevis, who owns AB Shellfish, in Staithes, said he reported symptoms seen in around 10 per cent of the lobsters he was getting in October to the authorities.

Mr Beevis, who owns a fishing boat and buys in shellfish, said: "I'm not a scientist but they are showing the same symptoms as what they were earlier this year. If you put them in water to try and bring them round, they roll onto their backs. I'm having to give them back or they go in the bin.

"The volume of shellfish aren't around to die now. You won't get a wash up of crabs, green, velvets or brown, as 99 per cent is gone in inshore waters. The only thing left to kill is lobsters. Then we haven't got a livelihood at all. If it affects the lobsters I might as well sell the factory and make it into a car park."

James Cole, Chair of Whitby Commercial Fishing Association, said: “It’s very frightening after what happened last year.”

An independent panel has been set up to probe the causes, but the Government remains of the view that pyridine is not to blame.

Last month a select committee heard from Dr Gary Caldwell, from Newcastle University, who found pyridine in sediment samples taken from multiple locations along the Tees.

However in a letter to the committee’s chair Sir Robert Goodwill, Defra Minister Mark Spencer said the Environment Agency detected no evidence of pyridine in water samples from October to December 2021. The EA concluded that the possible sources of pyridine Dr Caldwell identified "were not credible sources directly causing the impacts being seen".

Defra analysts are comparing landing data to assess the economic impact of the crab and lobster deaths. STDC said the work on the quay was “vital to unlocking thousands of jobs in Redcar and unleashing our green industrial potential” and it had “complied with the very highest legal standards and requirements” laid down in the licences.