Numbers down - maybe

It has been an interesting year for Brown Hairstreaks in Worcs with adult sightings generally down.  In contrast to 2015, we have had very few reports of nectaring individuals even at favoured spots like the hemp agrimony along the rides at Grafton Wood.  We presume honeydew in the canopy was more plentiful this year than last which may explain the difference.  The real test, of course, of a Brown Hairstreak season is not the number of adults seen but the number of eggs laid.  Our band of Thursday Streakers are yet to venture out with our first foray of the season not planned until 1st December when we shall be descending on Trench Wood near Droitwich.  The real test, however, starts the following Saturday when we commence our annual egg count at Grafton Wood.  This will be our 26th year of counting using the same methodology!  You can find out more about the Brown Hairstreak and indeed other butterflies found around the West Midlands in the new 'Butterflies of the West Midlands' book published earlier this year.  Copies can be ordered from the publishers at or at events organised by West Midlands Butterfly Conservation.  For further information about planned egg counts over the winter contact

Egg laying at Grafton - maybe!!

There seem to be far fewer sightings this year, than normal, at this early stage. I'm meeting a lot of people, who tell me that they have seen nothing and, on my visits to Gratin Wood, I've noticed far fewer individuals in flight, than normal. But they are around and, today was my best day of the flight season, so far. I saw four individuals: one flying over the old pond into oaks behind; one flying into the wood from the orchard and two females low down on the narrow path to the west of the old pond.
I think, but I'm not sure, that both of the females were ovipositing. They were crawling along young blackthorn shoots, fluttering low down and basking briefly, but I did not actually see egg-laying or find any eggs.

Egg laying at Grafton Wood (thanks to clearance work)

I was very impressed with the results of the shrub clearance near the old pond area. I saw 7 Brown Hairstreaks, today, all either in the old pond area or along the path to the west of the pond. Two of the females were definitely egg laying, however, in the area cleared either last year or the year before, opposite the pond. All the low flying, egg laying females were in this cleared area.

I think I have been missing a lot of sightings by looking around the area of blackthorn next to the pond, when most of the action is opposite the pond in the cleared area on younger blackthorn plants. The female below disappeared low in the blackthorn and I found two eggs, afterwards.

Most of my sightings were between 12.30 and 14.00pm. It was very windy, but they were active during the short spells of sunshine. I photographed four different females on the day. All in all, a very good day. I did notice that there was a lot of trampling in the cleared area. There are a couple of small "paths" through this area so please try to avoid trampling on the blackthorn saplings. Many thanks.

Early days at Grafton Wood

I read on the Grafton Wood blog that the first Brown Hairstreaks (including females) were seen on August 4th. I arrived last Sunday on a warm, sunny but windy day, feeling very hopeful of early season sightings. I walked the main rides for 3 hours, seeing a particularly strong showing of Gatekeeper, Brimstone and Silver Washed Fritillary. I was surprised that, although I saw 5 Purple Hairstreak (even on the ground), I did not see a single Brown Hairstreak in flight, at all, including around the pond area. My only observations were of two females, low in blackthorn, on the west side of the wood, either basking or nectaring on bramble.
Fortunately, one of the females was very photogenic and posed in virtually all the positions I wanted :-) for two minutes; then she was gone. There is something very special about our rarer woodland species. They spend most of their brief lives high in the canopy, rarely, if ever, descending so that we can fully appreciate their beauty. It is the fruitless hours or days that we spend travelling to, and searching these sites in vain, that makes these brief glimpses so very rewarding.

Any sightings yet

Anybody seen one of these yet. As the Purple Emperor season winds down, attention turns, hopefully, to Brown Hairstreak. I noticed on the Purple Empire that Brown Hairstreak were flying at Knepp, last week. As it is a long drive to my nearest site (Grafton Wood), I wondered whether they were out anywhere else yet. Many thanks.

Annual Transect Egg Count at West Williamston, Pembrokeshire

West Williamston’s annual egg count this year was carried out by 15 enthusiastic volunteers on a damp, grey Pembrokeshire day.  Travelling from all over south Wales.  The team also welcomed several new ‘hairstreakers’. 

The total number of eggs found was surprisingly high compared to reports of lower counts from other areas.  Blackthorn management has continued to be carried out on a rota basis by Nathan Walton, WTSWW officer and his volunteers, and it is worth noting that the areas where eggs laid were most concentrated correlates directly to the areas where most males were seen during August and September.

Aerial GPS locations of 2015 Brown Hairstreak eggs found along the foreshore transect (and beyond) with thanks to Stephen and Anne Coker

West Williamston SSSI Annual Brown Hairstreak Egg Count 
Sunday December 6th 2015. 
Blkthorn status   previous year
Blackthorn management
000 - 025
 Steven,  Anne,  Sarah & Gerry
v good

025 - 050
      “         “          “            “
v good

B Glade
      “         “        
V good

B Glade 2nd
      “         “         

050 - 075
      “         “          “            “

075 - 100
      “         “          “            “

100 - 125
Richard, Paul, Alan and Chiara

125 - 150
     “        “         “           “

150 - 175
     “        “         “           “

175 - 200
     “        “         “           “

Bracken Patch
Richard and Paul

200 - 225
Madeleine, George, Alan
v good

225 - 250
v good

250 - 275
      “     “     “       “      “

275 - 300
     “      “     “       “      “
v poor

Shallow Pool


300 - 325
David and John

325 - 350
     “           “          “           “

350 - 375
     “           “          “           “
  v poor

375 - 400
     “           “          “           “
  v poor

400 - 425

425 - 450
     “          “         “         “

450 - 475
     “          “         “         “

475 - 500
     “          “         “         “

This is the total written in diary on the day, after approximately 2 hrs

NB – Stephen and Anne Coker took GPS readings for all at end of December = 494
           Last year’s transect count total (2014) was 232

Egg survival summary from 2015 at West Williamston

Realising that I haven't yet written up the results of last winter's egg survival project I am posting a brief summary now before a much more satisfactory post with the results of our annual foreshore transect last month.                                                                                                              The chosen survey site was on the north side of top field, adjacent to the reserve’s small car park

The original aim of the survey was to try to assess the number of eggs predated by ‘unknown’ predators over the winter months, in order to establish base information for future surveys, including identification of possible predators.  

The survey was begun in September 2014, with fortnightly then monthy checks.  By March 2015  40 of the established 196 eggs were missing or predated, with a further 17 eggs found without tags. (A further 100 eggs were lost under different circumstances - see below).

The overall total of eggs surviving therefore was established as 78%. 
This compares well with survival counts carried out by David Redhead in the Midlands where survival rates appear to be slightly lower, being in the region of 75%. 
Could these be possible predators?
This survey was flawed and after 2 months there was a serious problem.
  • horses that graze the field broke managed to 'predate' several eggs along with the tender twigs they were on.
  • 85+ eggs were lost when the ‘over-enthusiastic’ contractor employed to top the meadow failed to see the young tagged Blackthorn and removed them too. These numbers were not included in the 196 eggs surveyed mostly by David Redhead, in a much denser area of blackthorn inside the fence.

This is an important learning curve, and the next egg predation survey will be carried out  with tighter limits and guidelines. Loss by horse and machine were not anticipated.
Encouragingly we established that the predation/egg loss was steady over the months from October to March.   In the past one of the 3 small sample survival counts had indicated that increased predation may have taken place very soon after the earliest eggs were laid i.e. possibly taken by  Warblers. 

These 3 old studies had resulted in  a higher survival percentage than the current study – they were all in the 80% band.  

Another late Brown Hairstreak sighting in S W Wales......further to Thursday's post, yesterday, I came across another female (in fairly fresh condition) flying below us on a habitat hotspot in Cwm Hiraeth, near Newcastle Emlyn in NW Carmasrthenshire - Teifi valley, where the species still thrives, largely due to high concentration of small holdings and low penetration of modern agriculture.

Anyone, who can contribute to other request on Thursday re growing blackthorn from seed, please share with us.

Whilst working out a coppicing plan, I disturbed a Brown Hairstreak this afternoon in a deep valley in a field of one of our few remaining southern Carmarthenshire sites. We've apparently gone from 56 sites in 2006 within 15kms of Carmarthen, down to just 6 still occupied. This includes one large site, part of which we manage.

On a related matter, although coppicing to regenerate via suckering is our main tool, the owner of one of the managed sites also wants to grow his own Blackthorn from seed (sloes) in his own tree nursery, so that they can be planted out into new hedges, and is asking for any tips on germination, growing etc. Does anyone have or can point me to suitable experience/advice please. Thanks.


I visited Grafton Wood yesterday for the first time since the cloudy, and hence somewhat disappointing, Open Day eight days ago. However it was a beautiful sunny day yesterday and I was rewarded with five sightings of separate female Brownies.

It was fairly chilly when I first arrived in the wood at 10:30, even though it was sunny, but it gradually warmed up and about an hour later I had my first sightings of two females in a large overgrown hedgerow, to the north of the main pond.

Half an hour or so later I bumped into Steve Williams and he told me he'd seen two females too, but in different locations to mine. We both went to investigate the area where he'd had his sightings and almost immediately found one of the females searching the blackthorn for suitable egg laying sites.

After crawling up and down various tiny blackthorn stems, this one (presumably?!) seems to have
got confused and I watched it lay an egg on a Field Maple sucker!

Walking back towards the pond, Steve then spotted another female flying and basking on a different stretch of hedgerow. No more sightings at the pond, although I'd earlier met someone who'd seen a female in an Oak tree there first thing in the morning at around 9:30.

At about 2:15 Steve and I both decided to call it a day and walk back to the car park. However
on the way back, Steve pointed out the area where he'd had his first sighting of the day - on a hedgerow roughly halfway between the church car park and the wood. Believe it or not, within a few seconds there it was - flying out of the hedge and stopping to bask just in front of us.

This was the fifth separate female I'd seen on the day, and shortly afterwards I spoke to another guy who'd had a sighting of a female right in the middle of the wood. That one, together with the one seen early on near the pond, plus my five sightings, meant that at least seven separate female Brownies had been seen in or near the wood yesterday. Evidence that the flight season is still very much alive!