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Common Blue

(Polyommatus icarus)

The Common Blue butterfly lives up to its name – it's bright blue and found in all kinds of sunny, grassy habitats throughout the UK! Look out for them in your garden, too.

Male Common Blue ©Zsuzsanna Bird
Common Blue butterfly (male)
Common Blue ©Ross Hoddinott/2020VISION
Common Blue butterfly
Female Common Blue ©Amy Lewis
Common Blue butterfly (female)

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Membership builds our community and gives us a predictable income, which lets us plan and sustain longer projects that can have a greater impact. The more members we have, the more we can do to protect the Sussex countryside and coast.

Overview

The most widespread of the blue butterflies, Common Blues are found in a variety of habitats, including heathland, woodland rides, grassy meadows, parks, large gardens and waste ground. Caterpillars feed on clovers, Restharrow, Common Bird’s-foot trefoil and related plants.

Key Facts

  • The male Common Blue has bright blue wings with a brown border and white fringe. The female is brown with a blue ‘dusting’ near the body. It has orange spots on the underside of its hindwings, whereas the similar Holly Blue has black spots. It is larger than the small and silver-studded blues, smaller than the rare Large Blue, brighter than the Chalkhill Blue, and lacks the black and white chequered pattern along the edge of the wings of the Adonis Blue.
  • There are typically two generations of Common Blues in a year, but if the weather is warm, there can be up to three broods over the spring and summer.
  • Wingspan: 2.9-3.6cm

Status

Common.

Seasonality

May to October

Video

Common Blue video

Common Blue butterfly on bird's-foot trefoil

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