Knowing what a hazel nut looks like after a hazel dormouse has eaten it is a great start to finding out if there are dormouse about and now is the perfect time to look for them. Yesterday I found my first of this year!
Hazel dormice leave a neat round hole with a smooth cut edge and teeth marks on the surface of the nut. This distinguishes them from very similar looking nuts that have been eaten by voles or wood mice. For more information go to this excellent guide from P.T.E.S. : https://peoplestrust.wpenginepowered.com/wp-content/uploads/2019/04/Help_us_find_hazel_dormice_generic.pdf
Dormice are probably more widespread than we realise but live at low densities (up to 10 per hectare depending on the habitat) so finding evidence of them can be challenging.