Common Blue

The Common Blue is the most widespread blue butterfly in Britain and Ireland and is found in a variety of grassy habitats.

The brightly coloured males are conspicuous but females are more secretive. The colour of the upperwings of females varies from almost completely brown in southern England to predominantly blue in western Ireland and Scotland, but the colour is variable within local populations with some striking examples. Unlike Adonis and Chalkhill Blues, the dark veins do not extend into white fringes of wing margins.

It remains widespread but there have been local declines within its range.

Size and Family

Family: Blues
Size: Small
Wing Span Range (male to female): 35mm

Conservation Status

GB Red List (2022): Least Concern
Butterfly Conservation priority: Low
European status: Not threatened

Caterpillar Foodplants

Common Bird's-foot-trefoil (Lotus corniculatus) is the main foodplant. Other plants used include: Greater Bird's-foot-trefoil (L. pedunculatus), Black Medick (Medicago lupulina), Common Restharrow (Ononis repens), White Clover (Trifolium repens), Lesser Trefoil (T. dubium).

Lifecycle

Habitat

Very common and found in a variety of habitats especially sunny sheltered spots. Examples of habitats include; downland, coastal dunes, undercliffs, road verges, acid grass and woodland clearings

It is also found on waste ground, disused pits and quarries, golf courses, and urban habitats such as cemeteries.