Suspected 'plague' blamed for Herefordshire crayfish deaths
A suspected outbreak of a deadly disease has killed dozens of endangered crustaceans in a waterway that runs through Herefordshire.
Large numbers white-clawed crayfish have been found dead in the Cwm y Caddo, a tributary near the Welsh border leading into the River Monnow.
The Environment Agency said it believed the cause was crayfish plague and has sent specimens for testing.
Anglers and waterway visitors are being advised to disinfect their equipment.
Chris Bainger, fisheries technical specialist for the agency, posted on social media about his concerns.
He said: "I'm significantly worried.
"I think sadly, it could be the end of the white-clawed crayfish in this area. It could become locally extinct.
"A non-native species is getting the upper hand and one that we don't necessarily want."
The plague, which is a mould, comes from the American signal crayfish which were introduced to Britain in the 1970s as a food source, but escaped into local waters.
Spores of the crayfish plague are very infectious but it has no health implications for humans or other animals.
The suspected outbreak could also have an impact on fish populations, Mr Bainger added.
"It could be very serious... we could lose a local population here and if it is confirmed as plague, it could be very easily transferred to other populations nearby.
"Native crayfish are in decline, we've got to do as much as we can to protect them."
Anglers and visitors to the waterway are being advised to wash boots and equipment, using disinfectant to remove any mud.
"What we say to the public, the best thing you can do is check, clean, dry," Mr Bainger said.
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