Home The Butterflies of Gloucestershire Species Habitats Conservation

Common Blue

Polyommatus icarus
Males, 18 June 1976 Female, 31 May 1976


Common Blues may be seen on unimproved grasslands, and in many other places where one of their larval foodplants grows. The commonest of these is Bird's-foot Trefoil (Lotus corniculatus). Other common foodplants include Black Medick (Medicago lupulina) and Lesser Trefoil (Trifolium dubium).

The foodplants grow in grassland, along woodland rides, and in shallow soils in places such as road and rail embankments, and old quarries. They may grow as weeds in garden lawns, and female Common Blues may sometimes be seen on lawns seeking plants on which to lay eggs.

20 June 1977

Conservation Issues

Adverse weather conditions have had a noticeable impact on population levels in 1998 and 1999, but the species is usually common and under no particular threat.

Flight Period

Late May and June for the first generation, late July and August for the second. Particularly early and late individuals are quite often encountered.


Throughout the area. It is the commonest blue butterfly, except in years when the Holly Blue's population cycle reaches its peak.