I think it must have been a crayfish, we're nowhere near salt water.

Daise1970, do you think it made it's way from Kent to Derbyshire

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As for it being on the park, well there is the river running though the park, but it was a fair way from water on the path by the tennis courts. Maybe it just fancied a change

. It was feisty wee man, whist I was taking it's photo it was rearing up and clanking it's pincers, but it had just been rolled over by a doodle so it's no wonder it was a bit peed off.
And Bid I'd have been terrified by an adder
