If we are unsure if dormice are present at a site, we might first carry out a nut search. This is an easy way to determine if dormice are present in an area before deciding to set up nest boxes. Where hazel is present in the woodland or hedgerow, we look for fallen hazelnuts that have been characteristically chewed by dormice.
A collection of hazel nuts chewed by dormice
Dormice give us a clue to there whereabouts by carving out a neat round hole in the nut shell, leaving a smooth inner rim before discarding it. Other small mammals, such as wood mice and bank voles, leave teeth marks in parallel lines.
Dormouse chewed hazel nut with a smooth inner rim and toothmarks at an angle to the hole
Dormice carve an almost smooth inner rim and toothmarks are at an angle to the hole on the nut surface. Wood mice leave parallel toothmarks on the inner rim and rough marks on the surface of the nut. A bank vole leaves neat parallel grooves on the inner rim, but no toothmarks on the nut surface. You can see illustrations of the different nibbled nuts on PTES’s ‘hazel dormouse fact file’, which are also shown below:
Hazel nuts are chewed differently by dormice, wood mice and bank voles. Photo credit: PTES
Please let us know if you would like to become a volunteer and join us on a nut search.