FOR IMMEDIATE RELEASE 27/10/2022
- New species of shrew identified in Britain confirmed by DNA analysis
- The greater white-toothed Shrew (GWTS) has been identified in Sunderland, North-East England
- If it becomes established, it will be the first new ground dwelling mammal species in Britain since the American Mink in the 1920s
- Photos of the species in this area date back to at least 2015
- The GWTS is known to be an invasive species in Ireland
A new species of non-native mammal for mainland Britain has been discovered in Sunderland in North-East England. In 2021 an unusual photo of a dead shrew was posted by Melissa Young on social media caught ecologist Ian Bond’s eye. Ian reached out to Melissa, pointing out that it looked rather like a White-toothed shrew.
Ian Bond explains ‘White-toothed Shrews look fairly distinctive with a head more closely resembling Finger Mouse or the Clangers than a normal shrew. The problem with that identification was that they have never occurred on the British mainland before!’
Following contact with Ian, Melissa kept the suspected shrew in her freezer so further tests could be undertaken. A subsequent DNA test, undertaken by Ecotype Genetics and Swift Ecology Ltd, confirmed it to be the greater white-toothed shrew. In Britain this mammal is only found on the Channel Islands of Guernsey and Alderney, although it is found on the other side of the Channel as far north as the Netherlands.
The Mammal Society’s Allan McDevitt comments ‘Given the rapid spread of the greater white-toothed shrew in Ireland, it is no surprise that it has eventually found its way to mainland Great Britain. This is a worrying development however as this invasive shrew is clearly associated with the local disappearance of the native pygmy shrew in Ireland. It is known to outcompete other species of shrews on other islands, so it is urgent that its distribution and potential impacts on other shrew species is quickly assessed.’
There is no indication of how the shrews arrived in Britain, let alone Melissa’s Garden. However, this is not the first time this has happened. In Ireland, greater white-toothed shrews started appearing in owl pellets back in 2007 with subsequent research showing it had been there for some time and was spreading rapidly. A further trawl back through Melissa’s posts show photos of White-toothed Shrews since at least 2015. This means this species could be quite widespread by now without anyone having noticed. Research is underway to find out just how far the shrew, nicknamed the Sunderland Shrew, may have arrived.
Melissa Young said “I’ve always kept my cats indoors to reduce their impact on wildlife, so I was really surprised when they regularly started catching shrews. Thankfully, most were able to escape without injury, but the opportunity to study those that didn’t make it has led to this invaluable discovery! The wildlife on your doorstep is simply amazing and I’m thankful to Ian for his observations and guidance which led to us taking a closer look at something most people wouldn’t look at twice.”
This discovery has shown just how important it is to submit records especially as mammals are some of the most under-recorded species in Britain. We encourage the public to submit any unusual shrew sightings with photos via Mammal Mapper (the Mammal Society’s app) or on iRecord.
Gavin Measures, Invasive Non-Native Species lead at Natural England said: “This is a fantastic example of how important it is to be vigilant for invasive species in our gardens, parks and green spaces. We greatly encourage everyone to take part in citizen science as it supports the vital work of Natural England to protect the environment. This non-native shrew has had a negative effect on the Irish ecosystem. Evidence of this species in the United Kingdom now requires further investigation to establish how widespread it is, and any possible impact on our small mammal community”.
Please note this press release was updated on 29/10/22
For further information please contact:
Sophie Webb (usual working times 09:00 – 17:30 Mon – Fri)
T: 02380 010983
- GWTS’s global distribution is confined to Western Europe and a small part of North Africa.
- The new population in the borough of Sunderland would be the furthest North it occurs anywhere in the world.
- On the continent it is known as the House Shrew because of its association with human habitation.
- It is an invasive species in Ireland where it is estimated to be spreading at 5km/year, an astonishing distance for a small mammal. Wherever it has spread in Ireland it appears to have led to the complete disappearance of the Pygmy Shrew, but it is unclear what its ecological implications would be in Britain, where the ecological landscape is more complex.
- Learn more about this species here.
- Photo available on request.
- Any non-native species sightings can be recorded online through iRecord or on the Mammal Mapper app.
- See the Mammal Society’s position statement on invasive mammals here.
- Shutter stock photos here.
About Ian Bond;
Ian Bond was secretary of Northumbria Mammal Group and the editor of the book, “Mammals, Amphibians and Reptiles of the North East”. He works for the Industry Nature Conservation Association, advising industrial companies on wildlife-related issues.
About the Mammal Society;
One in four of our native mammals is threatened with extinction, and many others are in decline. With Britain now recognised as one of the most nature-depleted countries in the world, urgent action is needed. The Mammal Society is working to give our wildlife a better future by:
- Keeping a constant watch on the conservation status of our mammals and making this information freely available
- Making conservation more effective by providing guidance on what to do and where to do it
- Educating the public and professionals about wild mammals, training people to survey them, and sharing the latest research
- Working in partnership to restore native mammal populations and re-establish functional ecosystems
The Mammal Society is the only charity with an interest in all British mammals. The Mammal Society’s conservation work is supported through the generosity of our supporters. A list of our current and past projects can be found here. To join the Mammal Society visit our website. Recent Mammal Society publications include: The State of Mammals in Wales and the Atlas of the Mammals of Great Britain and Northern Ireland.