Reports of another 'wash up' of shellfish on a beach on a stretch of coast where there has previously been a mass crustacean die-off is 'normal at this time of year', the Environment Agency has confirmed.

Visitors to Saltburn on Wednesday morning say they were met with the sight of dead mussels on the shoreline, starfish – some of which were barely moving – crabs and razor clams.

Read more: Crabs 'finally returning along coast' as politicians clash over crustacean deaths

The Northern Echo:

But the Environment Agency said it had not received any direct reports of the washed up marine life, but a spokesperson said it is “normal at this time of year” and high tides and recent stormy weather would “most likely be the cause”.

The previous mass die-off on the North East coast in late 2021 sparked a series of investigations with a conclusive cause yet to be established. 

In January, a panel of independent experts convened by the Department for Environment Food and Rural Affairs chief scientific officer Gideon Henderson concluded: “A novel pathogen is considered the most likely cause of mortality.”

However, the panel was “unable to identify a clear and convincing single cause for the unusual crustacean mortality”.

Four main factors were considered by the panel, a possible disease, a harmful algal bloom, toxic chemicals including pyridine, and dredging – but all were ruled out as a clear single cause.

A spokesperson for the Environment Agency said: "We are aware of wash ups of sea life on the beach at Saltburn. Given the recent high tides and weather conditions our experts have concluded it is a natural event, which is normal for this time of year.

"We can confirm the black substance washed up on the beach is coal deposit, which is not unusual for this stretch of coastline. This is likely to be in the intertidal system for a while given recent weather conditions so may continue to happen in the coming weeks and months.

"Creatures like starfish, razor clams and mussels occupy similar rocky habitat and are easily dislodged during storm events. And the physiology of juvenile flounder makes them vulnerable to being stranded on shallow gradient beaches such as Saltburn.

"While we know people are concerned, the combination of recent heavy swell, spring tides and onshore winds means natural wash ups will occur more often. If people do have concerns about pollution they should report it directly to our Incident hotline on 0800 807060."

Stuart Marshall, 58, who owns the colourful beach huts on the promenade, was mounting a clean-up on the sands.

He told the PA news agency: “It’s devastating. There’s starfish dead, clams, oysters and crabs.”

He said a large deposit of black debris on the beach – which some said was sea coal – had just arrived on the tide and was not normally there.

Mr Marshall, who has run the huts for almost seven years, said he does not believe the particles are coal, adding: “We do get bits of coal from time to time but not anything like this.”

The Northern Echo:

But one beach lover who was at Saltburn this morning said: "There were lots of mussel shells washed up that were empty, which suggests they were old and had been dead for some time - washed up by the storm yesterday.

"But walking along the beach this morning it was clear the starfish were still alive and had been carried onto the beach by rough seas."

Helen Whitworth, from Northallerton, North Yorkshire, was walking her border collie Drako on the beach.

She said: “This black area is not usually here.

“Usually it’s a really beautiful beach.

“There’s all sorts of debris here.

“I’ve come down for a lovely walk with the dog and it’s such a shame to see all of this today.”

Earlier this week, scientists have said they are "finally seeing shore crab and edible crab juveniles return" along the Teesside coast.

Environmental Secretary Thérèse Coffey said: “We did make the judgement that we wouldn’t try and pursue any further research, however, we did say we would respond to similar mortality events and CEFAS has not received any reports of mortality events since the original 2021 incident.

“After decline, my understanding is that landings started to return to typical levels and I know that in other parts of the North East there has been drops in the catches of prawns overall in that area.

“The review has indicated that there hasn’t been a particular change in that regard so there’s no obvious particular things to get into but as I said at the time, if there are reports of similar crab crustacean incidents experienced in that 2021 incident CEFAS will be involved pretty much straight away to determine it.”