Freshwater Crayfish

I have been doing some Otter Survey work on rivers throughout Limerick and Tipperary over the last two weeks.  Yesterday while surveying a small tributary of the Mulkear River, I came across loads of freshly half eaten Caryfish on rocks and on banks along the riverside.  These have obviously been eaten by Mink and Otters and when I checked under a few small boulders in the river, I found many live Freshwater Crayfish like this one below.