www.ukbutterflies.co.uk

Careful Paul your Whitter searching isn't supposed to be bad for your health I like your handy way of spotting larva without the need for a ladder

Have a goodun

Wurzel

I think your research and findings has shown quite clearly Paul that the WLH is not just under recorded, it is MASSIVELY under recorded. I think you're also probably doing a fine job educating folk and I include myself in that. Thanks for the details you sent me recently. If I check it out I'll let you know. In the meantime keep up the good work.

Great tutorial, Paul. Very helpful. It’s interesting to see the pattern of feeding and as you say, with elm leaves now unfurled, this is the best time to go looking.

Thanks all for your comments

Recent Doings

Old Winchester Hill 5.5.2019 - After having a result with the White-Letter Hairstreak larvae I spent a further hour soaking up the rest of what this site had to offer. I notched up 4 season firsts in low numbers with several Grizzled and Dingy skippers as well as solitary Common Blue and Small Copper with a couple of delightful Green Hairstreaks for good measure. West Wood 11.5.2019 - I come here specifically for Pearl Bordered Fritillary. My visit this year was better timed than previously catching some fresher individuals than I have done in the past. The weather also was ideal for capturing this species, cloudy and cool with short spells of warm sunshine. This is not a well known site for this species, but gone are the days when previously I had the place to myself. Today there were at least 3 other observers. I counted at least 7 Pearl Bordered Fritillaries all of which seemed to be males. The job of finding a Duke Of Burgundy, which also occupy the same area of regenerating woodland, was a little more challenging. After an hour and a half on site I was beginning to think I would not see one. Before that thought had even left my mind one appeared in front of me in almost exactly the same spot as in previous years. Also on the wing here several Grizzled Skippers, Speckled Wood and just as I was leaving the Brimstones had woken up with half a dozen males seen whilst walking back to the car.

That is a cracking Duke - a great reward for all the hard searching - I swear that Butterflies have an innate telepathic capability I often find pouring a coffee or having a mouthful of my extra hot Lime Chilli Pickle has the same affect

Have a goodun

Wurzel

Paul Harfield wrote:...I come here specifically for Pearl Bordered Fritillary. My visit this year was better timed than previously catching some fresher individuals than I have done in the past. The weather also was ideal for capturing this species, cloudy and cool with short spells of warm sunshine.

Yes, Paul, cloudier, cooler conditions are better for this species. Their flight season coincides with quite a spectrum of potential weather, but hot sunny days are not ideal.

Congratulations for the Common Blue. They seem rather shy this year!

Thanks Wurzel and David for the comments

More Recent Doings

I recently 'rescued' a Garlic Mustard stem from a verge that gets routinely mowed. On close examination the rescued stem had surprisingly 11 Orange Tip eggs crammed onto its small flower head plus one further egg laid on the underside of a leaf several tiers down from the flowers. I had assumed this egg was from a Green Veined White. All the eggs have now hatched. Unfortunately a spider unseen by me had managed to occupy the flower head and seems to have feasted on all the Orange Tip eggs/larvae as none seem to be present. However, the one hatched larva on the underside of the leaf seems NOT to be Green Veined or Small white

White-Letter Hairstreak

Whilst it is still possible to find actively feeding larvae, some will already be looking for a suitable place to pupate. The larvae will stop feeding, change colour and wander before settling in a suitable position. Over recent days I have encountered several in this pre-pupation stage and today a rescued larva has pupated. Conveniently these larvae have demonstrated a variety of different approaches to finding a 'suitable place':

Interesting report Paul - I'm wondering which strategy will work best and what agents will do the testing The chamber is the most hidden but then birds could learn that there's a tasty morsel hidden away in between the leaves so it could almost be an advertisement Great work.

Have a goodun
Wurzel

It really is a superb skill you have, Paul, being able to locate them at this stage. Thanks again for increasing our knowledge of this species.

Thanks for the comments Wurzel & David

More recent doings..

In The Garden

A significant event in my garden this year is that my Buddleia globosa has flowered for the first time. I have spent several years unknowingly pruning it in completely the wrong way and wondering why it never flowers. I now know what I should be doing and have been rewarded with a generous show . It has also attracted the attention of several other admirers. White-Letter Hairstreak

I was recently invited to a private site to look for White-Letter Hairstreak larvae. On 25th May I accompanied Andrew Brookes (Hants & IOW BC species champion for the White-Letter Hairstreak) to the site where he had planted Elms of various types and cultivars 20 years ago (as trials for DED resistance). To date no evidence of the butterfly had previously been found at this site. I was initially doubtful of finding larvae due to the timing of our visit, I suggested we were perhaps a week too late. However, there was plenty of feeding damage evident on various trees particularly a White Elm (Ulmus laevis). After an hours searching I managed to locate a single White-Letter Hairstreak larva on a Japanese Elm (Ulmus davidiana var.japonica). This was a magical moment. He then suggested we visit another site not too far away where further Elms had been planted 10yrs ago. Again White-Letter Hairstreak had not been recorded there thus far. This site is a rather more exposed location but I managed to locate a pupa on provence Field Elm on this years growth. Unfortunately the pupa had been predated but nevertheless proving that the butterfly has reached both locations. Meanwhile at home I patiently await the imminent emergence of White-Letter Hairstreak from x2 rescued larvae.

Great observations, Paul. The clock is now ticking for WLH emergence. I expect the first to be around the weekend after next.

David M wrote:Great observations, Paul. The clock is now ticking for WLH emergence. I expect the first to be around the weekend after next.

Thanks David - Last year the earliest record down here in Hampshire was 2nd June and in 2017 it was 9th June I think. If I can find a gap in the weather I had my fingers crossed for some action this weekend. Nothing doing today though, it is all a bit wet,windy and unpredictable .

Last year Pauline and I had some discussion about pupation habits of the White-Letter Hairstreak and the possibility that they do in fact pupate in leaf litter in the ground. This is contrary to most British references about the pupation of this species. I was recently shown this video https://www.youtube.com/watch?v=vdDNGF2HDr0 the most interesting bit is at the end.
Interestingly, it only refers to pupation on the ground for this species with no mention of leaves or twigs as a chosen position for pupation. It was recorded in southern France. Could this be something driven by climate/temperature ie the hotter it is the more likelihood that the larva will go to the ground to pupate? Any comments are welcome.

Hi Paul, what we need is irrefutable proof that they pupate in leaf litter (when not captive reared). I have been doing my bit and I know you have too. Great video which goes a long way to support our views. It is quite possible that the variation in choices of pupal location are part of a transitional phase which could be down to climate change or something else. I'll keep in touch tho it may now be a bit late for this year.

Paul Harfield wrote:..Last year Pauline and I had some discussion about pupation habits of the White-Letter Hairstreak and the possibility that they do in fact pupate in leaf litter in the ground. This is contrary to most British references about the pupation of this species. I was recently shown this video https://www.youtube.com/watch?v=vdDNGF2HDr0 the most interesting bit is at the end.
Interestingly, it only refers to pupation on the ground for this species with no mention of leaves or twigs as a chosen position for pupation. It was recorded in southern France. Could this be something driven by climate/temperature ie the hotter it is the more likelihood that the larva will go to the ground to pupate? Any comments are welcome.

Those VarWild films are as good as anything I've ever seen. Thanks for highlighting this one, Paul, as I hadn't hitherto seen it.

Like you say, the most interesting bit is near the end, when the butterfly emerges from the pupa within the leaf litter.

Sunday 9.6.2019 IBM/Lakeside Cosham

This site is always reliable at providing my earliest White-Letter Hairstreak sightings, but it has become less user friendly over the last few years. However, they have now mown/cleared a wide walkway through the grass and trees which has restored access to the best area. When I arrived, just after lunch, the sun was frustratingly hidden behind cloud despite half the sky being blue. The first thing that caught my eye during the cloudy spell was my first Marbled White of the year. There was not much else going on but I had a feeling that my target was there just waiting for some sun. A few Meadow Browns stirred and a beautiful blue female Common Blue posed nicely as well as few other inhabitants. After waiting an hour and a half for the sun to reappear I was eventually rewarded with a single White-Letter Hairstreak . This moment marks the beginning of an intense few weeks following this species around Hampshire.

What is the creature on the leaf below the adult hairstreak, Paul? It looks very like a w-album cat, though it seems to be on the upperside of the leaf.

Guy

A great find Paul - is that the first in the UK this year? It's been a few years since I've been to Cosham - I've been keeping half an eye on the Bentley Whitters - if only I had more time I'd like to get there again

Have a goodun

Wurzel

Padfield wrote:What is the creature on the leaf below the adult hairstreak, Paul? It looks very like a w-album cat, though it seems to be on the upperside of the leaf.

Guy

Hi Guy
To be honest I had not noticed it, this was a long range and highly cropped shot. I would have thought it was unlikely to be a WLH larva, but it is possible I suppose. Or maybe a gall of some description or other leaf blemish, we will never know.

Wurzel wrote:A great find Paul - is that the first in the UK this year? It's been a few years since I've been to Cosham - I've been keeping half an eye on the Bentley Whitters - if only I had more time I'd like to get there again

Have a goodun

Wurzel

HI Wurzel,
A White-letter was reported from Durant's Park, Enfield on Saturday 8 June and another one from Sussex on the same day.

ATB
Peter