A new type of trap is being designed to combat the spread of an invasive crab that is threatening Norfolk's waterways. 

The Norfolk Non-Native Species Initiative (NNNSI), an organisation which tracks and fights harmful plants and animals, is under way with plans to roll out a network of traps to capture Chinese mitten crabs

Chinese Mitten Crabs are native to East Asia but were introduced to the UK in 1935 where they have since spread to rivers, canals and estuaries up and down the country.

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The crabs pose a serious threat to the local ecosystem by damaging riverbanks, competing for food with native species, blocking vital water outlets and damaging fishing equipment with their claws. 

Eastern Daily Press: The crab's spread is being tracked across the countyThe crab's spread is being tracked across the county (Image: NBN Atlas)

But the NNNSI is taking drastic steps to "stop them in their tracks".

Liam Smith, the initiative's nature recovery officer, said: "We are in the early stages of designing a monitoring trap which will be placed along the north Norfolk coast to see how far they have spread.

"The design is currently in the early stages but it hopes to target mitten crabs as they are not very good swimmers and rely on walking along the bottom of the waterways."

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He added that no new crab sightings were reported in Norfolk over the winter because of high water levels and mixed weather but that did not mean there were any fewer of them in locations where they are known to be.

"As always, the constant efforts to monitor and control invasive species in Norfolk rely heavily on input and support from members of the public and landowners," Mr Smith said. 

"If people spot any suspicious crab sightings, please contact us at NNNSI@norfolk.gov.uk."