Hedgehogs 2012 Calendar. This Hedgehogs 2012 Calendar features 12 cute and captivating images of the popular garden and hedgerow inhabitant the Hedgehog. Hedgehogs belong to a group of mammals called 'Insectivores' – they simply hunt and consume insects. Hedgehogs are solitary animals which are mainly nocturnal and feed primarily at night. By the time a hedgehog is 3 to 4 weeks old, it already has over 3000 spines on its body! Enjoy this prickly character through the 12 images in this Hedgehogs 2012 Calendar to take you through the New Year!