Red Admiral (Vanessa atalanta): This beautiful butterfly can be seen at almost any time of year. Not strictly a hibernator, it overwinters in a torpor, rather than full hibernation, becoming active during warm winter days. Another that uses nettles as its principal larval food plant. In late summer males set up territories, defending them against other butterflies and occasionally small birds! They may regard human presence as an intrusion too; but if you stay still they will probably settle again. UK population boosted by immigrants during the autumn.