Looking for the Brown Argus

Last week, with the help of a local insect expert, I went with some volunteers to Lundy Bay to carry out our weekly summer butterfly transect. This time though we were particularly looking for the brown argus, which has been seen at Lundy Bay before, but only ever in very low numbers.


They are very difficult to tell apart from the female common blue butterflies, so we used a net to carefully catch the ones we suspected were brown argus. We were in luck, we found two! And next to a female common blue that we also netted, we did ‘spot the difference’!

Click on the photo below to see clearly the differences yourselves....


As far as we are aware, no more than half a dozen brown argus have been spotted at Lundy Bay at a time. The brown argus has two adult broods a year and the average lifespan of an individual adult is four days. They tend to live in small colonies and the females are fussy about which plants they lay their eggs on. This is why we don’t find many at Lundy Bay.


If you want to find out more about the brown argus, or any other butterflies, check out: britishbutterflies.co.uk

Sarah - NT Ranger North Cornwall