Hazel nuts are popular with many small mammals (our native dormouse, muscardinus avellenarius, is called the hazel dormouse for a reason). And the way a nut is opened can tell you who’s eaten it. This is particularly handy for telling if dormice are present, as you’re very unlikely to see one.

So, starting with the easy one. It takes strong jaws and teeth to split a hazel nut. So if you find a discarded nut shell split in two, or shattered, the nut has probably been eaten by a squirrel.

Bank voles also have big, strong teeth, so can bite rather than nibble through to the kernel. Quite often they will leave an irregular, roundish hole in the shell. They tend not to leave lots of teeth marks on the shell near the hole, unlike mice.

Now we get to the tricky part: distinguishing between nuts eaten by apodemus