New Zealand Flatworm Survey results

Our citizen scientists have helped to identify and record sightings of New Zealand flatworms, helping to map the spread of this introduced species across the UK. Verified sightings are due to be transferred to the official national database (the National Biodiversity Network), leading to an over 20% increase in the total number of records nationwide.

What have we found?

 The data submitted by OPAL participants shows that:

  • Most of the reported sightings of the New Zealand flatworm came from the northern half of the UK, although confirmed records came from as far south as Birmingham and near Luton
  • Five other non-native flatworm species were also recorded, principally the Australian flatworm
  • There was a strong correlation between presence of New Zealand flatworms and the absence of earthworms, showing that the presence of New Zealand flatworms has an impact on the earthworm population
  • There were fewer molehills where New Zealand flatworm was present, suggesting that the loss of earthworms after New Zealand flatworm invasion had also impacted on moles, which prey on earthworms

Whilst looking out for New Zealand flatworms, our citizen scientists also spotted another invasive flatworm -  Obama nungara

See results on the OPAL Data Explorer

Explore the OPAL New Zealand Flatworm Survey results and draw your own conclusions. Use the OPAL Data Explorer to:

  • Map sightings of New Zealand flatworms across the UK
  • See whether New Zealand flatworms have been recorded near you

View New Zealand Flatworm Survey results on the OPAL Data Explorer (opens in new window)