Green Hairstreak


A tiny little butterfly and our only true green species in both sexes. It is very overlooked but not thought to be declining in numbers in fact several new colonies have been discovered in the last 10 years notably in West Cumbria. Some colonies are very small and can be in short discreet areas along roadside verges. The larger colonies are found on bogs and mosses and often contain vast numbers. Good places to search are where its larval foodplant grows and in Cumbria that tends to be Bilberry though it will also use Rockrose and Gorse. As with other hairstreaks it gets its name from the row of white dots in a curve across both wings, but some are very well defined whereas others have hardly any white dots. Neither sex will open its wings whilst at rest.

Where to look

Meathop Moss, SD445819 in south Cumbria is perhaps the best UK colony with literally hundreds flying on a good day. Roadside verges are worth searching where there is Bilberry for example the verges around the Killington reservoir near the M6. The raised peat bogs on the Solway coast, Hallsenna Moor NNR, NY064006 in the west and the woodlands at Centre Parcs near Penrith are also good.

Record distribution and images.

When to look

Very late April until the end of June

Recorded flight times. Cumulative records. Annual frequency.