Blues

The term blue is a partial misnomer as not all of the species are blue. The species that are blue it is often only the males, as the females tend to be brown.

Many of the blue species have caterpillars that produce a sweet liquid to which ants are attracted too. The ants 'milk' the caterpillar for the liquid, but in no way harm it. The ants carry the caterpillars to foodplants close to the ants’ nest. The caterpillars benefit from the protection of the ant colony.

Many populations of blue species diminished with the introduction of myxomatosis. The crashing of the rabbit population drastically affected the species' habitats. The habitats void of rabbits meant that plantlife was not kept closely cropped, this condition was required for their foodplants and the ants to thrive.

  Common Blue Polyommatus icarus

   Holly Blue Celastrina argiolus

  Silver Studded Blue Plebejus argus

Common Blue Polyommatus icarus 

The males are blue but only on the upperside. The males’ undersides are brown and grey with black spots, the wings are edged with orange and black eyespots.

The female is dark brown with a blue tinge around the body. There are orange dots on the wing fringes. The females’ underside is similar to that of the males.

There are usually two broods. The food plants are trefoils, clovers and vetches.

Photograph by Alan Griffiths

Holly Blue Celastrina argiolus

Both sexes of the holly blue have similar colouration. The uppersides are a lilac blue, with the females having a larger brownish fringe. The undersides are a paler blue with black dots.

There are usually two broods. The foodplants are the flowers, buds and berries of holly and ivy.

As both these of these plants fruit and flower at different times of year, the first brood feeds on holly the second ivy.

Photograph by Alan Griffiths

Silver Studded Blue Plebejus argus

There are large differences between the sexes of the silver studded blue. The upperside of the male is a silvery blue, the wings edged in black with a white fringe. The upperside of the female is a dark brown, the wings edged in orange patches and fringed with white.

The undersides of both sexes are pale brown with orange and white patches and brown spots. The female has more spots.

There are usually two broods. The food plants include vetch, heather and bird’s foot trefoil.