The mystery cause of fish spontaneously dying in a North East watercourse has been revealed after baffling environmental experts investigating the matter.

For the last couple of months, the Environment Agency has been investigating a small number of dead and dying salmon and sea trout after they were first reported in the lower Coquet in the Warkworth and Felton areas.

Reports have increased over recent weeks with numbers now more than 50. 

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Environment Agency fisheries experts have carried out an investigation and concluded it appears to be a fungal infection, which is a recurring issue in this area.

According to experts, some of the fish appear to be already suffering from the infection when they enter the river from the sea, while others have developed it while in the lower river.

The Northern Echo: One of the infected salmon. Picture: ENVIRONMENT AGENCYOne of the infected salmon. Picture: ENVIRONMENT AGENCY

Low river flows combined with the high-water temperature and other factors such as a number of weirs to pass are causing the fish to be stressed, which makes them vulnerable to infection and allowed it to take hold.

Richard Jenkins, environment agency fisheries team leader, said: “This is something we have seen happen before, quite frequently, in this area and we have previously carried out significant laboratory analysis to understand more about the issue.

The Northern Echo: The EA have now confirmed that a fungal infection is behind the fish deaths. Picture: ENVIRONMENT AGENCYThe EA have now confirmed that a fungal infection is behind the fish deaths. Picture: ENVIRONMENT AGENCY

“We will be doing further testing on the affected fish next week to confirm it.

 “We believe it to be an environmentally driven natural infection, which affects fish which are stressed.

“We understand this is distressing for people to see and are grateful for the reports we have received.”

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