Brown Hairstreak in Hampshire
Male Brown Hairstreak underside
Male Brown Hairstreak
Brown Hairstreaks Mating Photograph by David Levy
Brown Hairstreak caterpillars are notoriously hard to find once they have hatched out and start to feed on the Blackthorn leaves.
Female Brown Hairstreak underside
Female Brown Hairstreak
A chance to find (4) Brown Hairstreak eggs on a fork of a Bush is very rare indeed. I have found three at Noar Hill, this is probably several females which have selected this fork in which to lay their eggs. They are very vulnerable to predation but the female will lay enough eggs to invest in the species existence the following year.
A male Brown Hairstreak looking down from his lofty perch after a good 'fight' with other males on a lecking tree. This is good behaviour to look out for especially very early in the morning in warm sunshine. A Good fight can involve up to a dozen males, and can last a good few minutes.
Lecking trees are quite easy to find especially early in the morning I've witnessed them at Shipton Bellinger and at Noar Hill, a high tree normally Ash trees where many males will compete for territories, to get a front row seat as it were to grab a lady when she emerges and mate with her. Some of these high clashes can be quite spectacular involving many males who do battle for many minutes chasing each other. They can also be witnessed in the rides at Shipton Bellinger like in the picture above the high tree will often hold spectacular aerial displays in the early morning giving you a chance to see the rare male Brown Hairstreak at close quarters .
The picture in the centre of the page is of a country lane very close to Creech Wood where eggs of the Brown Hairstreak have been found over the past few years : The map left is of the map of Hampshire showing where the main areas (tetrads) of the main Brown Hairstreak colonies may be found. The map on the right is a quite detailed map showing an area around Soberton where the Brown Hairstreak is found normally every year. A good count of up to eighty eggs have been recorded in the area.
Blackthorn and Country lanes
Good homework is the key to finding the Brown Hairstreak butterfly, the adult not so much as its quite hit and miss whether one will turn up, weather has to be warm and sunny (goes for most butterflies I know!), and the blackthorn mainly along secluded country lanes and old hedgerows in fields, have to be between one and two year old growth, best look at young bushes growing up to waist height is probably ideal. After a female has passed through she will have layed a good many eggs, as they are predated by mice,shrews,and beetles all predate the chrysalis but enough eggs are left to hopefully keep a viable population going in the area where it can be found. Many hedges of Blackthorn are trimmed back in the winter again leading to a heavy loss of the eggs and caterpillars, so looking for the eggs can be quite hard in the winter months, but it's a very exciting prospect to find them in an unknown area, and looking for the adult in the the following late summer months is always a challenge, but well worth it. They have turned up in peoples gardens in the Meon Valley , and in and around Andover, thus leading to more inquisitive searches and expanding its range over a few seasons if they are found year after year.
Brown Hairstreak eggs are quite easy to find on Blackthorn in the winter. This is a close-up looking like a sponge in close-up
Large tracts of Blackthorn behind Portsdown Hill are well worth looking for Brown Hairstreak eggs. Several female Brown Hairstreaks were observed in the late summer here.
The Brown Hairstreak is found along old paths and byways and along tank tracks on the Army ranges at Shipton Bellinger.
The army ranges on the opposite side of Shipton Bellinger at Bedlam Plantation are a good area to look for the Brown Hairstreak, along with the Wall Brown Butterfly
There is normally a good turn out for the Brown Hairstreak field trips annually. Normally when the female is found feeding on a plant normally Hemp Agrimony it normally stays feeding for many minutes without moving, giving good photo opportunities.
Blackthorn is chosen as its foodplant, and the female selects young growth normally 2-3 year old growth, normally up to hip-level. Best time to find any eggs layed in the autumn is in the winter when the leaves have all dropped off.
Scrub which isn't cut on a yearly basis are good areas to find the eggs in the winter.
Looking for the Brown Hairstreak eggs at a location in the Meon Valley in January.
Sightings on Portsdown Hill
Photograph of Brown Hairstreak female on Portsdown Hill: Richard Jones
The Brown Hairstreak is one of those butterflies where you can never be sure you will go out and see it, and sometimes it's just a fleeting glimpse unless you are an expert in the way it flies then a glimpse will always make you wonder whether you have seen one or not. That's why it is imperative to visit Blackthorn thickets in the winter/early spring to see if there are any eggs present. Invariably you will be disappointed, but like so many sites just over the last few years, in the past decade the Brown Hairstreak has expanded its range....it's possible that it was always present, there have been very hard hitting egg hunts in the past few years turning up the species in some areas where it was never present or was overlooked. It has probably been very present on Portsdown Hill as over the top of the Hill facing North there are so many Blackthorn thickets dotted all over the area, especially in and around Creech Wood, Wickham, and along the old railway line and the River Meon. The photograph of the female taken by the Ranger on Portsdown Hill said that this female was not observed egg-laying, as the south facing side of Portsdown Hill has very little in the way of Blackthorn...its all on the north facing side. Just to see the female was a triumph, like last year 2021 when several females were seen in and around the public house The Churchillian.
I have found it quite easy to follow a female Brown Hairstreak on Blackthorn once she has selected twigs in which to lay her eggs. Here she is feeling the twig with her abdomen, once she has selected a twig she will her eggs normally in a fork of a Blackthorn bush.
At Noar Hill where there are good numbers of Brown Hairstreaks in good years, they can be seen at certain 'flint' pits year after year.
Wild Blackthorn hedges like this one on the left are the kind of areas which are worth looking at in the early autumn where a female Brown Hairstreak could turn up and start to lay her eggs. Thickets like these are more common than you think consequently the Brown Hairstreak could be more commoner than we realise. This is just one stretch of Blackthorn on the north side of Portsdown Hill.
As well as Hemp Agrimony, Oxford Ragwort, Thistles, they also like Blackberries to feed on, this is a good time to see the males which do not come down too often to ground level.
Brown Hairstreaks are quite acrobatic and this female had suddenly run out of Blackthorn and was just about to take off and look for another suitable area to lay her eggs.