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New Zealand flatworms


The numbers of our native earthworm are declining thanks to this invasive worm - it loves to feast on them.

Find it on: undisturbed ground, under stones, logs and pots. Prefers cool, damp habitats.
Time to act: all year round


The New Zealand flatworm was first introduced to the UK in the 1960s, although it has never become as great a problem as was originally feared. It's purple-brown on top, and flat and pointed at both ends. When resting it coils up, is covered in mucus, and is about 1cm wide by 6cm long, although when extended it can be up to 30cm long. It lives on earthworms, covering them in digestive juices to dissolve them before sucking them up. The larvae of ground beetles prey on flatworms.

Researchers are eager to know of new sightings. Should you discover a possible flatworm in your garden, please take a digital photograph and email it to When taking photos, place an object such as a pencil, or a key, alongside the creature to provide scale.


The numbers of our native earthworm are declining thanks to this invasive worm - it loves to feast on them.


Check sites where they like to hide undisturbed - for example under stones and pots - and dispose of any you find. Where there's one, invariably you'll find more. Where they are present, spread a sack on the ground, weigh it down and keep checking if more are hiding beneath. Eggs are usually found between June and September. Destroy the worms by squashing or dropping them into salty water.

Discuss this problem

Talkback: New Zealand flatworms
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gailms 24/11/2011 at 15:28

I have a cert in horticulture studied in 1993 in west lothian, while there I became aware of the problem that we have in britain with the new zealand flat worm. I recently bought a house and found one in the garden under a plant pot, since then whilst digging and creating I have not found or see one earth worm !!!!!!!! and today while raking up some bark chippings found 2 cocoons HELP

gailms 24/11/2011 at 15:28

Hi its Gailms again , Do you are you able to answer any comments Thank you

icecrystalserp 24/11/2011 at 15:29

was quite disturbed to find nz flatworms how ever when they were found we were actually hunting slugs under logs closely followed by our new call ducks which when seeing we had something in our hands promptly gobbled them up too!!!this incidently is near saltash in cornwall how far are they distributed in the uk?icecrystalserp

Joiner1 24/11/2011 at 15:29

I've found 104 so far this year under a carpet tile next to the compost heap, dont understand what they are all living on as I cant find any worms.
I did read somewhere that beetle larvae eat flatworms and have started log piles all over the gardn. I'm in the clyde valley

pepper1 24/11/2011 at 15:29

we have read reports people finding a couple of flat worms,we are in the highlands of scotland,and we are finding hundreds of them ,any advice on how to get rid of them please hope you can help thanks

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