Best time to see: late Jul to end May

Key facts

Spectacular large butterfly with 'eyes' on each wing

Habitat: anywhere in countryside or garden, but commonest around woods

Common resident throughout southern Britain, reinforced in some years by migrants from the continent

Recognition

Mainly chestnut upperwings with blue and black 'eyes'; underwing grey-black like tree bark

Fly freely and powerfully, feeding and breeding wherever they find suitable conditions

Teasels and brambles are favourite nectar sources and, in gardens, buddleia bushes; wingspan up to 7 cm

Lifecycle

Pale green eggs laid in batches in May under the leaves of stinging nettles

Groups of dark spiny caterpillars feed conspicuously on nettles, scattering to pupate in trees or dense vegetation

After feeding through late summer/early autumn, adults hibernate over winter, mainly in hollow trees and woods