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Invasive Crayfish Discovered in UK River, Threatening Native Wildlife
17 Nov, 2025
Summary
- Children found an American signal crayfish in the River Tame in Uppermill, UK
- The invasive species outcompetes and spreads crayfish plague, devastating native white-clawed crayfish
- The crayfish poses a severe threat to the local ecosystem, food chains, and water quality
On November 17th, 2025, children playing at a park in Uppermill, UK, came across an American signal crayfish crawling from the River Tame. This invasive species, first introduced to the UK in the 1970s, has now been spotted in the area for the third time this year, also appearing in the Huddersfield Canal and River Beal.
Local authorities and conservationists are deeply concerned about the threat the American signal crayfish poses to the region's native wildlife and river ecosystems. The invasive species outcompetes and spreads a deadly crayfish plague that devastates the native white-clawed crayfish population. Additionally, the crayfish's fast breeding and aggressive burrowing habits can destroy riverbanks and disrupt local food chains, as they "eat almost anything" from aquatic plants to fish and frogs.
The Mersey River Trust, along with the Environment Agency and United Utilities, is taking action to protect the small remaining population of white-clawed crayfish in the area. Combating invasive species requires constant vigilance, and public awareness can help document more sightings for local authorities. Preventing the introduction of non-native species in the first place is crucial for maintaining the ecological balance and ensuring a cleaner, safer future for the region's waterways and wildlife.
