The quagga mussel, first spotted by Environment Agency teams carrying out routine water quality testing on the River Wraysbury, has now been confirmed in a total of nine locations in the south east.
Over the last few weeks the Environment Agency has stepped-up its monitoring on the River Thames and reservoirs in the local area to investigate the extent of the problem and the distance that the quagga mussel has spread.
Environment Agency teams up and down the country have been briefed to be on the look-out for the quagga mussel. The quagga mussel can significantly affect freshwater ecosystems and can outcompete native mussels. It can also block water pipes and smother boats’ hulls.
The Environment Agency is continuing to work with a range of partners including Thames Water, Angling Trust and local angling clubs, to ensure that people check, clean and dry any equipment that has been in contact with water.
Sarah Chare, head of fisheries, biodiversity and geomorphology at the Environment Agency, said:
“These newest discoveries only go to show just how prolific the quagga mussel is. We are monitoring the extent of its spread and working closely with partners to ensure they are aware of it and know what action to take.”
Like the zebra mussel and killer shrimp the species comes from the Ponto-Caspian region – an area around the Black and Caspian seas in south-east Europe.
Simon Earl, head of water production at Thames Water, said:
“Another invasive species is the last thing we need clogging up our network. But we have a lot of experience in dealing with zebra mussels, which are similar to quagga mussels, and there is no threat to the quality of the water we supply to our customers.”
“We’ll continue to monitor the situation and would urge those using our reservoirs to help us stop the spread of the mussels by reporting any sightings and following Environment Agency advice on cleaning equipment.”
The quagga mussel has now been confirmed at the following nine locations.
To the west of London:
- Wraysbury Reservoir
- River Wraysbury
- The Queen Mother Reservoir
- Queen Elizabeth II Reservoir
- Queen Mary Reservoir
Bessborough Reservoir
- In the Lee Valley:
- Warwick East Reservoir
- Warwick West Reservoir
- William Girling Reservoir
The Environment Agency will update the distribution map on its website if new discoveries are made.
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