Sunday, February 24, 2013

February Survival

Delighted to report that there has been no mortality this month (with 4 days still to go) amongst larvae hibernating in the wild.  That's a fair achievement as losses are highest during the late winter period.  There's still another 3 weeks to go, though, before we can relax, but it does look as though the predation level is relatively low this winter.  It may well be that tit numbers are down in the forests, after poor breeding success last year.  Hope so.  I'll check the BTO data. 

Here's today's picture of the greatest iris larva ever -

He is dreaming the spring...

However, my female Brimstone wasn't there.  I suspect she moved during the four reasonably mild and sunny days we had in mid Feb, as she was hibernating in a very warm spot.  I've marked her so may see her flying in the spring.

Meanwhile, it has been reported that National Trust shops are selling a mobile of garish plastic psuedo purple emperors.  Any NT shop peddling such outrageous and deeply blasphemous garbage must be petrol bombed. 

Friday, February 22, 2013

Another Pupal Case!

Done it again!  Found the remains of another pupal case in the wild.  Spotted one of last year's leaves spinning round on the gentle breeze of eve, or whatever the poet called it, high up in a large old sallow (a broader leaved x reichardtii hybrid).  The leaf was attached only by silk.  Sure enough, the basal part of a pupal case was evident. 

This drama took place on the south slope of Toys Hill, near Westerham in NW Kent.  This is not the first record for here as the local NT warden was assaulted by a male in his garage nearby at Emmets back in early July 2009.  He still carries the bruises. 

Friday, February 15, 2013

More Tosh!

Yet more tosh taking the name of the world's premier butterfly in vain - The Riddle of the Purple Emperor is a ripping yarn about a precious jewel in the days of the Indian Raj. Regrettably, I was bored by the end of the first page. The thing needs rewriting, into the ripping tale of an expedition into the depths of the New Forest during the great summer of 1893 in pursuit of Iole herself... Here's a quote from one of the entomological journals from that hot dry summer: 'I followed the bed of one of the streams in search of water to drink, and was disappointed in not finding enough to quench my thirst, not a pool being left, but I was repaid by the sight I witnessed: the said bed of the stream for more than a mile was literally crowded with butterflies...' They were mainly adippe, paphia and camilla, with a lot of hyperanthus, etc.

Monday, February 4, 2013

Recent Doings...

I checked the hibernating iris larvae in / around Savernake Forest over the weekend, and the hibernating Brimstone. 

Sadly, one larva has apparently been lost since I visited with John Woolmer in mid January, probably to bird predation.  This was a light brown larva on a grey-green branch, the third larva down featured in John's recent eulogy.  I was always worried about this larva as it stood out like a sore thumb. 

It might, possibly, have moved as another on the same tree has moved 40cm since mid Jan, from a stem scar up to a leaf bud.  However, if it has then it's travelled >3m, which is a mighty long way in mid winter.  I have only recorded four larval movements in hibernation in four winters, from three larvae. 

We are now entering the period of main predation. 

The really good news is that my hibernating Brimstone is alive and well.  She must have been buried in snow.  She got knocked off the rush stem she was hanging on to, but has resettled into a beech leaf on the ground below.  Most of the leaves of the minor bramble bush she was originally in have now been eaten by deer, and it's good to know that she hasn't been eaten.  Incidentally, each time I have checked her she hasn't been comatose, but has been moving around a little (last Saturday, due to disturbance by the wind).  It wasn't possible to obtain a reasonable photo as there was too much vegetation in the way.

The Edwardian poet-naturalist Edward Thomas (who visited Savernake with his wife Helen nearly 100 years ago) wrote: 'It is not yet spring.  Spring is being dreamed, and the dream is more wonderful and more blessed than ever was spring.  What the hour of waking will bring forth is not known.  Catch at the dreams as they hover...' (The South Country, 1909).  Those words could almost have been written with this Brimstone in mind.

Meanwhile, here's the latest picture of the most beautiful hibernating iris larva ever seen -

Sunday, February 3, 2013

Hibernating Emperors

From John Woolmer - Jan 15th 2013

Now is the winter of our discontent made glorious (Richard the Third)
                                           Brine hating could describe winter tactics (11)

There is something mystical about being in the company of real experts. To see Adrian Hollis (world correspondence chess champion) look at a disputed endgame and dissect it in seconds; to hear Rob Sheehan ( former Times bridge correspondent) analyse a difficult hand; to listen to the Amadeus quartet play Mozart in a lofty abbey with perfect acoustics ; to watch Jim Laker and Tony Lock demolish the Australian second innings at the Oval in 1953; to listen to the great mathematics writer CV Durrell, at the age of ninety, interrogate the writers of the  once fashionable School Mathematics Project with razor sharp precision; to hear the evangelist; to see Michael Green’s slide of the Sea of Galilee where he spoke from a boat audibly to someone standing half way up the hillside (see Mark 4:1) illustrating the veracity of the Gospel accounts – all this is quite ethereal.

Seeing the paintings of the great Venetian master Carpaccio, in a small church, recounting the engaging legend of St Jerome and the thorn in the lion’s paw; looking at the extraordinary variety of the three hundred carvings in the ceiling of Shepton Mallet Parish Church (and noting the Puritan bullet holes in some of the angels’ wings); listening to George Eliot’s Middlemarch being beautifully read on Radio 4 preceded by a lovely Beethoven bagatelle – all of these could be added to my list!

Savernake Forest was bathed in bright winter sunshine. I used to visit Savernake with my parents. We loved to read the text on the monument, deep in the far side of the Forest far from the A4, which gives thanks for the recovery of King George 111 and also declares that the Earl of Ailesbury received his elevation through merit (and, by implication, not bribery!). Later, with Karl Bailey, I realised that the obelisk is a favourite meeting place for male Purple Emperors. They squabble around the monument like courtiers wanting to take precedence around the King. How fitting that the Emperors should gather round a monument celebrating the recovery of the mad King who probably suffered from an illness which, amongst other things, causes purple discoloration of urine (porphyria).

There I met Matthew Oates, the PE expert, and he showed me many treasures. His knowledge, and expertise and knowledge of appropriate poetry, is of a similar quality to that extolled above. He showed me many trees around which males gather and various sallow bushes, in different parts of the forest, on which females lay their eggs. One highly favoured bush has been visited in each of the last four summers. This year there have been many fewer eggs laid. He pointed out six hibernating Emperor Caterpillars – all with strikingly different colouration perfectly matching the willow branches and buds against which they rest for the long winter.  Their colours change gradually over a five week pre-hibernation period. They appear to select resting places which match their remarkably varied colouration. Some of Matthew’s photographs in British Wildlife June 2012 show an even more striking camouflage effect. All known larvae have survived since entering hibernation in November; one has caused Matthew consternation by moving. The rest have remained motionless trying to avoid the sharp eyes and hungry beaks of the long-tailed tits and other predators. Curiously, more eggs do not necessarily mean more butterflies. There is a theory that a relative abundance of hibernating caterpillars leads to greater searching by the efficient predators. It also seems that those which choose cracks in the wood rather than camouflage near buds do better.

Another dangerous time is in the early spring when the caterpillars move to await the opening of the buds and the arrival of food. Matthew calls this ‘the airport departure lounge’ syndrome and it is a time of great danger for the hungry waiting caterpillars. How Matthew finds these minute caterpillars (and he has tracked down a number of other ones in more remote parts) is something of a mystery – evidently he finds eggs and young caterpillars in the autumn which can give themselves away by nibbling at leaves in a very characteristic way. Then he looks nearby for signs of the perfectly camouflaged hibernating insects. Ideally, he likes to lie horizontal and look upwards scanning the bark of every sallow bush with his powerful glasses (O happy servant he in such a posture found! –as a curious hymn line puts it). Dog walkers, he remarks laconically, look perplexed. 

He also produced, high up in a sallow bush, the empty base of a chrysalis from last summer. This was discovered, high up a tree, by examining any leaves which hadn’t fallen through powerful binoculars. Then low down, he showed me a Female Brimstone hibernating in a small thicket of bramble. All that was lacking was the perhaps mythical icicle hanging down from the tip of her wings! What a perfect winter day! In the next few days, winter arrived with massive snowfalls making the bright sunlight on January 15 seem even more marvellous. I wonder what the rest of the year will bring…..
Hibernating PE larva Savernake, 9mm
Hibernating PE larva
Hibernating PE larva 9mm
Hibernating PE larva
Hibernating PE larva 9mm
Hibernating PE larva
Hibernating PE larva 9mm
Hibernating PE larva
Empty pupal case
Hibernating Brimstone