There could be other signs, though: feeding/feeding stations are the easiest to spot, then there are burrows and latrines and footprints. Worth having a good look for these.
You will be first to know re Water Voles. I have had an email back from WT they think ears are to big for the dead creature to be a wv but checking with someone else.
Just posted a couple of Water Vole pics from this morning into the gallery, been on holiday so I just had to get down to the canal. 2 adults and 2 juveniles out and about - lovely
There was a full-length shot, too, but I didn't post it as I know there are a few children who look at my blog and I didn't want to distress them. The body was intact but a bit manky.
If you ever see another unidentified dead mammal like the one you posted, try and get a look at its teeth.
