Invasive demon shrimp discovered in waterway

An invasive species of shrimp has been discovered in a protected waterway, raising concerns for native species and the wider ecosystem.

The demon shrimp, larger than the native equivalent and with a distinctive stripy back, has been discovered in the Holy Brook, a tributary of the River Kennet which runs through Wiltshire and Berkshire.

The charity Action for the River Kennet (ARK) is urging those who encounter the species, which can outcompete native species, to report it to them.

The charity's education and outreach manager Anna Forbes said it was also imperative that river-users follow the government's Check, Clean, Dry guidance to stop the demon shrimp spreading further.

"Check, Clean, Dry is really important. Demon shrimp eat little fish, fish eggs, are less effective at cleaning the water than native species and are highly aggressive. They don't belong in the mix," she added.

The guidance calls for increased awareness of the problem and the need to thoroughly dry all equipment and clothing after activities on or in the water.

The shrimp, originally from the Caspian Sea, are believed to have travelled to UK attached to boat hulls before being spread locally by kayakers and anglers unaware of their presence.

The discovery is part of a wider problem in the South West. Invasive American signal crayfish remain a problem at Prior Park Landscape Garden in Bath, having previously caused millions of pounds worth of damage.

Garden and outdoor manager Piers Horry said that once invasive species get settled in an environment they are difficult to remove.

"We've tried to eradicate them but we were surprised how quickly that population boomed [after the damage was repaired]. We're looking into other methods, such as potentially introducing predators, to address the problem.

"Becoming a local action group can also help and there is lots of support from authorities like the Environment Agency."

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