Butterflies - Brown Hairstreak (Thecla betulae)
The Brown Hairstreak is a single brooded species being on the wing from late July to early September, with the males emerging first. The elusive adults occurs in low numbers over large areas. Males may congregate around a 'master tree', usually an Ash near the breeding colony.
The adults feed primarily on aphid honeydew which coats the leaves of Ash although adults can sometimes be seen feeding on flowers. The females may be found feeding on Fleabane (Pulicaria dysenterica), Hemp Agrimony (Eupatorium cannabinum) and Brambles (Rubus fructicosus) between periods of egg laying.
The adult male Brown Hairstreak lacks the golden orange flashes on the upper-forwings shown in the photo right.
Ash Brownies - The Official Brown Hairstreak Blogg by Warwickshire Committee Member Gillian Thompson is a great place to learn more about the Brown Hairstreak butterfly and its distribution in Worcestershire and Warwickshire.
- Larval Food Plants
- Key Sites
Blackthorn (Prunus spinosa)
Areas of extensive hedgerows or woodland edges where Blackthorn is present in large quantities and where minimal hedgerow damage through mechanical trimming occurs. Mechanical flailing of hedgerows during the autumn months can have a devastating effect on this species with the number of eggs which hatch the following spring being greatly reduced.
It is possible that the Brown Hairstreak may occur in very small numbers in the south Warwickshire area. Recent egg searches on the border with Worcestershire have resulted in some eggs being found in our region although adult butterflies are yet to be recorded.
In 2010 a single adult was observed at King's Coughton, confirming the presence of the species on the Warwickshire / Worcestershire border.
Resident in Warwickshire.
The presence of Brown Hairstreak eggs in Warwickshire (around the Princethorpe Woodland Complex) is thought to be due to conservation action at the nearest known breeding colony of Brown Hairstreak centering around Grafton Wood near Flyford Flavel, Worcestershire.
During 2009/10, several Brown Hairstreak eggs were located on Blackthorn centered around Ryton Wood Meadows and an adult butterfly was seen briefly in 2009. Butterfly Conservation Warwickshire has begun monitoring of this species in order to establish its true distribution in the area.
In 2010, 7 adult butterflies were observed in the Ryton Wood Meadows Reserve area and for the first time, a single adult was recorded on the southern limit of the County at King's Coughton. This individual being part of the Grafton Wood colony.
Attempts at re-introduction
Between 1968 and 1972, a colony of Brown Hairstreak was present in the region but its sudden disapearance resulted in an attempted reintroduction at Yarningdale Common in August 1982. The project was however unsucessful.
A photographic slideshow displaying various images of the Brown Hairstreak is currently in development.
Details of how you can supply your own photographs for display here will be made available soon.
The flight chart below is based on observations of the adult Brown Hairstreak butterfly in Warwickshire between 2005 and 2008. Peak periods are shown in dark green.