A species of mussel native to the Ukraine has been found in the UK for the first time, posing a potential risk to the local water supply, and endangering native wildlife and the environment.
The Quagga mussel, which is almost indistinguishable to the native zebra mussel, has been found at Wraysbury reservoir near Heathrow Airport.
According to the Wildfowl and Wetland Trust (WWT) the Quagga congregates in large numbers, blocking pipes and causing flooding. Once established, it is practically impossible to eradicate from reservoirs.
In a recent report the Centre for Ecology and Hydrology (CEH) predicted: "The invasive alien Quagga mussel (Dreissena rostriformis bugensis), not yet established within Britain but anticipated to arrive within five years, has been identified as the top-ranking threat to our natural biodiversity.
"It poses a high risk because it is an ecosystem engineer with the potential to disrupt the ecological function of freshwater environments."
A spokesman from The Department for Environment, Food and Rural Affairs (Defra) told the BBC: "It is important that we take action to address the threats posed by invasive non-native species. Users of our waterways can help with this by checking their equipment and keeping it clean and dry."
Quagga threat to Las Vegas
In the US the Quagga is threatening to block water supplies to the city of Las Vegas having formed colonies in the Hoover Dam.
The Quagga was inadvertently introduced to the US after being sucked up in ballast water for ocean-going ships which arrived in the Great Lakes in the 1980s. They are now present in 29 states.
A single Quagga lives for around five years, producing five million eggs. Of these around 100,000 will reach adulthood, so one Quagga can produce half a billion adult offspring. There are now thought to be 10 trillion Quagga around the Great Lakes. Quagga eat plankton, reducing the food available to native fish, which die out in huge numbers.
It is not known how Quagga reached Wraysbury reservoir, but the impact on the WWT's London Wetland Centre a few miles downstream could be disastrous.
"These tiny mussels can be devastating but look so innocuous," said Wildfowl and Wetlands Trust spokesman Jeff Knott. "Quagga mussels are likely to indirectly cause suffering and death for hundreds of thousands of native animals, fish and plants and cost millions of pounds in tax and water bills to protect drinking water supplies."