First Brown Hairstreaks of the season

2/9/2025

GH and BG set out early for Transect 22 in classic British summer conditions – a mix of sun and cloud, interrupted by a brief rain shower and accompanied by an almost constant strong south-westerly wind. Unsurprisingly, the blustery conditions held numbers down, leaving us with a lower-than-average late-season count. Even the usually reliable Meadow Browns were noticeably fewer than last week.
The day’s highlight, however, more than made up for the dip in numbers: our first Brown Hairstreak of the year, spotted and photographed beneath the oaks on Hill Wood Field. Moments later, a second individual may have zipped past us in the same section – a fleeting but tantalising possibility.
The Brown Hairstreak is always a special find. It is the last of our regular butterfly species to emerge each season, with adults often proving elusive because they spend much of their time high in the treetops. To find one low down is a rare treat – and a memorable reward for a windswept walk.

Count details:
68 Meadow Brown
10 Common Blue
5 Small White
4 Small Heath
4 Brown Argus
3 Chalkhill Blue
3 Small Copper
1 Brown Hairstreak

Count summary:
98 butterflies from 8 species.

For more info on these species visit
butterfly-conservation.org

This week's butterfly

Brown Hairstreak (Thecla betulae)

The Brown Hairstreak is the last butterfly to emerge in the UK each year, with adults usually appearing from late July into September.
Females lay their tiny white eggs on young blackthorn twigs, where they remain visible all winter until hatching in spring.
Although widespread in parts of southern England, adults are rarely seen because they spend most of their time high in the tree canopy, only occasionally coming down to feed or lay eggs.