AN investigation into the deaths of crabs and lobster in the North East has finally been concluded.

DEFRA and partner agencies have completed their investigation of the cause of the sea life which were found washed up on the North East coast between October and December last year.

Read more: Authority responds to damning remarks made by fishermen over dead crabs

Following significant testing and modelling to rule out possible causes, Defra and partner agencies found that the deaths of the crabs and lobsters potentially resulted from a naturally occurring harmful algal bloom.

From the evidence found during the investigation it is unlikely that chemical pollution, sewage or infectious aquatic animal diseases were the cause of the deaths, according to the investigation.

No traces of chemical contaminants have been found that could have caused an event of this scale. Follow up survey work carried out by the Environment Agency on the 18th and 19th of January 2022 has also shown live healthy crabs present in the area, albeit in reduced numbers.

A review of dredging activity and water samples found no evidence of a link between the disposal of dredged sediment and the deaths.

The sampling of sediment that has been licenced by the MMO for disposal to the designated sites off the Tees confirmed that no chemical determinants exceeded concentrations (‘Action Levels’) that would be harmful to marine life

A further review of dredging, disposal activity and water samples found no evidence of a link between the disposal of dredged sediment and the mass crustacean deaths.

This investigation was a multi-agency response, involving Defra, the Environment Agency, Centre for Environment, Fisheries and Aquaculture Science (Cefas), North Eastern Inshore Fisheries and Conservation Authority (NEIFCA), the Marine Management Organisation (MMO), Food Standards Agency (FSA), UK Health Security Agency (UKHSA), to identify what could have caused the event.

Evidence gathered by Government scientists and multiple agencies throughout this investigation will continue to be collated and studied. While this is no longer an active investigation, the agencies will continue to work with local fishers and remain on standby to respond if further events occur.

The joint investigation has not found any evidence of a food safety risk from healthy fish and crustacea, including crabs and lobsters caught off the North East coast. While there is no food safety risk from eating crabs that have been caught in waters off the North East coast, it is unsafe to eat dead or dying crabs found on the affected coast.

The public are encouraged to continue report any incidents of concern to the EA helpline on 0800 80 70 60 and industry are encouraged to contact NE IFCA on 01482 393 515 or


Keep up to date with all the latest news on our website, or follow us on Facebook, Twitter and Instagram.

You can also follow our dedicated North Yorkshire Facebook page for all the latest in the area by clicking here.

For all the top news updates from right across the region straight to your inbox, sign up to our newsletter here.

Have you got a story for us? Contact our newsdesk on or contact 01325 505054