Flatworm survey

© Paul Hetherington

Get involved in our flatworm survey

We are concerned about the invasion of non-native flatworms in the UK, and we need your help to find out just how far they have spread.

Please get involved in our backyard flatworm survey – it is easy to do, and only takes 10 minutes!

How to get involved

Spend 10 minutes searching for flatworms in a nearby outdoor space – it could be your back garden, or somewhere you visit during your daily exercise.  Look in damp, dark places such as under wood, stones and plastic, and underneath plant pots.

If you find a flatworm please take a picture.

Then please answer our questions below to send us your photo and information on your survey.  Please complete the questions whether you have found a flatworm or not – we are interested to know where flatworms aren’t as well as where they are.

What is a flatworm?

Land flatworms have smooth bodies covered in mucus and range in shape from flattened to cylindrical.  Unlike earthworms and leeches, flatworm bodies are not segmented, and they can be separated from slugs by the lack of tentacles and completely smooth bodies. Land flatworms can be found in dark, damp places such as in the soil, leaf litter, at the bases of plants or under logs, stones and other objects.

There are at least three native species of land flatworms in the UK, but more than ten non-native species. We have an identification guide to flatworms here.

Why are we interested in finding out more about flatworms?

Non-native land flatworms have been accidentally introduced to the UK in imported pot plants and newly arrived species continue to be discovered.  Once introduced these flatworms can reproduce rapidly, cannot be eradicated, and pose a risk to native soil invertebrates such as earthworms by feeding on them.

Scientists have found that in some areas, non-native flatworms can reduce local earthworm populations by 20% – this could have a huge impact on soil health and agriculture, as well as our native soil wildlife.

By taking part in our survey you will help us to better understand how non-native flatworms are spreading around the UK, and you may alert us to a newly arrived species.

Obama Flatworm (Obama nungara) © Richard Lewington

Want to take part?

Submit your findings here, then after review we’ll publish your finding on the map below.

  • DD slash MM slash YYYY
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  • (please take a look at our identification guide to the right)
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    Accepted file types: jpg, png, Max. file size: 100 MB, Max. files: 10.
    • This field is for validation purposes and should be left unchanged.

    Explore the map and click on the circles to find out more about the survey submission.

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