Common Blue

The weather has been a bit miserable the last few days.  Sunday promised a spell of sunshine, so we headed thirty miles west around the coast and visited one of my favorite butterfly sites, the Iron Age hill fort, Warham Camp.  It was a good decision, the sun shone and it was very warm with the lightest of breeze.  Perfect conditions for finding the Common Blue (Polyommatus icarus).

Male Common Blue

The Common Blue is the UK’s most widespread member of the ‘Blue’ family, it can be found on most sunny grassland sites where the food plant of the caterpillar, bird’s-foot trefoil or lesser trefoil, occur.  It is a small butterfly with a wingspan of 29-36mm (1 1/4 – 1 1/2 inches).  Like some other Blues the females upper wing is mostly brown edged with an orange band, though some colonies have a lot of blue colouration.

Common Blue under wing

The under wing, like most Blues, has a lot of eye spots.  The old English name was Blue Argus, Argus in Greek mythology was a god with a hundred eyes.  The blue colouration can vary, some are so vivid as to be almost violet.

Several Common Blues were seen including egg laying females, this is the first brood, there is a second emergence in late July.

And as we drove home the fog once more rolled in off the North Sea.