Native white-clawed crayfish used to be present in most Norfolk rivers but have been decimated by invasive signal crayfish and are now extinct in most of their range, and the three remaining populations are threatened by the proximity of signal crayfish. As part of their work to protect and restore internationally rare chalk-fed rivers, Norfolk Rivers Trust (NRT) aimed to:
- Use eDNA to track both native and invasive crayfish in UK rivers.
- Gain insight into crayfish distributions in order to inform management decisions.
This involved detecting remnant populations of WCC so that they could be protected, while also ensuring that potential WCC reintroduction sites were free from the invasive signal crayfish.