Mike Eaton, who curates Fiveways Corner, has sent in two images and some video of a Signal Crayfish lurking in the stream at Fiveways.
Apparently it’s an American import that was introduced to the UK and which has now overrun the UK’s native species with smaller claws. This one seems to be immune to the high levels of phosphates and nitrates that are in the stream.
Regardless, a nip from it will hurt. You have been warned.
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