Invasive species: Why quagga mussels are a menace
A new species of mussel has been found in the UK which could be hugely damaging to British wildlife.
Quagga mussels originate from Eastern Europe and experts believe they could cause the death of thousands of native animals and plants.
They also block water pipes which can cause flooding and infect water supplies.
Dr David Aldridge from Cambridge University spoke to BBC Breakfast about the threat.