Butterflywatch: Can the blues be in clover once more?

Many butterfly names are inaccurate - the Essex skipper, for instance, is found far beyond that county - and some are becoming more so. The common blue is not common and lepidopterists are keen to identify its surviving colonies.

We can help by looking for this blue-with-a-hint-of-mauve butterfly (the female is more brown than blue and harder to identify) during the last weekend of Butterfly Conservation's Big Butterfly Count. Everyone is urged to spend 15 minutes recording butterflies, logging results online. So far, I've counted small and large whites in abundance but no common blues.