Brown hairstreak butterfly

Brown hairstreak ┬ęPhilip Precey

Brown Hairstreak butterfly

┬ęPhilip Precey

Brown hairstreak

Scientific name: Thecla betulae
The brown hairstreak is an elusive butterfly that spends much of its time in the treetops feeding on aphid honeydew. It is found in woodland and along hedgerows where blackthorn grows.

Species information


Wingspan: 3.6-4.5cm

Conservation status

Protected in the UK under the Wildlife and Countryside Act, 1981. Priority Species under the UK Post-2010 Biodiversity Framework.

When to see

July to September


The largest of the UK's hairstreaks, the brown hairstreak is an elusive butterfly that spends most of its time either high in the tops of large ash trees (called 'master trees'), or among thick hedges. It is found at woodland edges and along hedgerows in southern England from late July until November. Adults feed on honeydew from aphids, while caterpillars feed exclusively on blackthorn.

How to identify

The brown hairstreak is a large hairstreak, with brown upperwings and small 'tails' protruding from the hindwings. Females have a brilliant orange patch in the top corner of each forewing. The underwings are a distinctive bright orange, with two white lines streaked across them.


Found in scattered locations in southern England and Wales.

Did you know?

Female brown hairstreak lay conspicuous, round, white eggs on young blackthorn shoots. Looking like blackthorn leaves, the older larvae are extremely well camouflaged and feed only at night.

How people can help

The Wildlife Trusts work closely with farmers and landowners to ensure that our wildlife is protected and to promote wildlife-friendly practices. By working together, we can create Living Landscapes: networks of habitats stretching across town and country that allow wildlife to move about freely and people to enjoy the benefits of nature. Support this greener vision for the future by joining your local Wildlife Trust.