www.ukbutterflies.co.uk

I wanted to bring your attention to the Elm Report, produced by Andrew Brookes. This is an excellent publication, and is specifically targeted at assisting the White-Letter Hairstreak. A downloadable copy of the report is available from the Hampshire and Isle of Wight BC branc website at:

http://www.butterfly-conservation.org/h ... ation.html

Cheers,

- Pete

Peter

Thanks for the reference to the Elm Report. Very interesting reading. I always assumed English Elm was indigenous. Presumably the WLH was resident before the arrival of the Romans? Perhaps the core colonies are in the old Roman towns?

The resistant varieties hold out some hope for the future of the WLH.

best wishes

Tom Dunbar

eagle wrote: The resistant varieties hold out some hope for the future of the WLH.

I certainly hope so. My understanding is that the WLH has particular requirements regarding the time of flowering, bud burst etc. However, since these Elm species are not indigenous, then we need to get to the point where the trees are mature enough to produce flowers, so that we'll then know what time they flower etc. in the UK. And whether or not this is in sync with the needs of the butterfly (and its various stages).

But definitely a step in the right direction!

Cheers,

- Pete

Back in the 1970s, whilst searching Laneside Blackthorn Hedgerows well removed from Black and Brown Hairstreak localities, I located a single egg of the White Letter on Blackthorn.

A fine specimen of a female W-L-H was reared on potted Blackthorn. The larva emerged around the first week of March and fed up on the Blackthorn Blossoms only moving to leaves when well grown.

Observations of wild W-L-H ova on local Wych Elms (Glos) at around same time showed hatching around first week of March well in advance of leaves. The newly hatched little larva entering the Elm Blossoms and developing seeds which appear well before the leaves.

How easy is it to find the ovum of White-letter Hairstreak?

I have tried looking for Purple and Brown Hairstreaks the last couple of winters, but have yet to have any success.

From the Hants and Isle of Wight sightings page at

http://www.hantsiow-butterflies.org.uk/sightings.html

where Andy Barker summarises things as follows:

"If hard core butterfly enthusiasts can’t wait for the new recording season to start, I can suggest searching for hairstreak eggs. This is an ideal time of year for searching blackthorn bushes for Brown Hairstreak eggs. The pin-head sized white eggs are fairly conspicuous, and typically found near the junction of new growth and old growth on the outer twigs of established bushes, or else look on suckering growth near the base of a hedge. The best places to look are the Noar Hill – Selborne Common area, or else the hedgerows in the vicinity of Shipton Bellinger, NW Hampshire.

If you want to search for eggs of the more widely distributed Purple Hairstreak, the stormy weather of recent days will have broken off a few branches from the crown of large oak trees. This provides ideal material to search. The eggs are usually found near young buds, but it may take a while to get your eye in.

Hardest of all will be to find White-letter Hairstreak eggs, and unless you know some elms where you’ve seen the butterfly, it really will be a needle in a haystack task. If you know a group of elms where you’ve seen the butterfly, search the lower branches and look out for a small “flying-saucer”-like egg near fresh buds. Only really worth looking if you know the elm flowers. Good luck. These searches can be successful, but you need to have patience".

Personally, I think Purple Hairstreak are the easiest to find - mainly because they're the commonest species of the 3. Brown Hairstreak are fairly easy to find in good locations. I've never found White-letter myself.

Cheers,

- Pete

They say the proof of the pudding etc...

As Pete was writing his last report I was out at a very wet and windy Noar Hill searching for my first Brown Haistreak Ova.
Can you imagine my delight when I actually counted four.
Definitely exciting and a good way to walk off the excesses of the festive season.
Highly recommended.
Have included a couple of shots for your enjoyment.

Cheers


Colin

Matsukaze wrote:How easy is it to find the ovum of White-letter Hairstreak?

I have tried looking for Purple and Brown Hairstreaks the last couple of winters, but have yet to have any success.

It's a great help to have good eyesight ... which I used to have..

Like so many things in life, once you've found the first and you get 'your eye in' you wonder how you failed before. The ova of the White Letter Hairstreak can be like that. If you find one on the lower branches of an Elm, usually tucked into a small bark fissure or on or close to winter buds, search the other parts of the tree you can easily reach ~ there will almost certainly be others. A good tree will usually support a 'colony'. Who knows how many ova are on those branches higher up well out of reach..

In my experience, the ova of the Brown Hairstreak can be easy to find as the pearly white colour shows up well against the black bark of their foodplant in winter. They are rarely laid high on the bush and a more reliable indicator of the insect's presence in a locality than looking for the imagines in late summer. I have found them in places where I've never seen the butterfly.

I once found their unmistakeable eggs on a leafless Sallow bush in late January a few inches away from a little Purple Emperor larva hibernating in a twig fork! There was a Blackthorn thicket nearby.

During winter, search the lower reachable branches of mature oaks in areas where you've seen the Purple Hairstreak back in the summer. Ova will be tucked up on or in the larger clusters of winter Oak leaf or flower buds or closeby. Again, when you find the first you'll learn so much that the next one will be so much easier to locate. During late July, if you watch carefully you can observe the females carefully creeping around and selecting those larger terminal leaf buds to lay their ova. Binoculars can help here..

Years ago, I reared a few Brown Hairstreaks from wild ova and sleeved the five butterflies over a potted Blackthorn. The larvae were well fed on the growing plant and I provided good food for the adults so that they would become sexually mature. When they'd been in the sleeve for a couple of weeks, I released them in their old woods. When I removed the netting covering the potted Blackthorn I found hundreds of ova thereon. Some of the little twigs were white with them! All were fertile and several friends were able to rear this little butterfly for the first time. I returned a few to their original haunt. Even so, it took a while to glue the little off-cut twigs to the Blackthorn.

What really amazes me about the hairstreak eggs in winter is that any are able to survive the countless flocks of small birds which pass through the thickets and trees most days throughout the winter looking for food. Some of these flocks contains dozens of Tits ~ Long-Tailed being my favourites ~ and they sytematically 'work' the thickets over. Many ova must get taken but obviously some survive.

Same winter observations are true of hibernating Purple Emperor larvae which are often fully exposed to birds and weather relying only on cryptic colouring to survive.

By the way, the ova of the Green Hairstreak are not difficult to find ... but, not in winter. In the Cotswolds where the insect is often abundant, a favourite foodplant is Rock Rose and their eggs can be found on that plant. Also, Bird's Foot Trefoil. A freshly emerged Green Hairstreak is a joy to behold.

Cotswold cockney wrote: "Years ago, I reared a few Brown Hairstreaks from wild ova and sleeved the five butterflies over a potted Blackthorn. The larvae were well fed on the growing plant and I provided good food for the adults so that they would become sexually mature."

It is commonly held that Brown Hairstreak (and other similar species) feed on honeydew mainly on ash and oak. Has this been verified in the field? Despite much checking of ash buds over recent years I have failed to clearly identify any 'sticky' residue which I might assume to be honeydew - often on twigs where Brown Hairstreaks have just been seen 'feeding'.

Is the literature correct? We now question many of the previous assumptions, 'master tree' theory in particular.

What form did the 'good food' take fed to the adult BrHs by CC? Will they come to flowers in captivity?

I managed to locate a Black Hairstreak egg this Winter but that follows an abundant year in 2006 for the species.

best wishes

Tom Dunbar