An Early Season?

Purple Emperor larvae made considerable progress during April and are currently in an unusually advanced state.  

In Savernake Forest yesterday, April 28th, I saw nine larvae: three were in the 4th instar (L4), with one nearly half-way through that stage; the other six were busy skin changing to L4. 

Savernake is a 'late' site. Larvae will be far more advanced in Sussex and Surrey (probably all in L4, with perhaps some approaching the L4-L5 skin change).  

An early flight season remains on the cards, though much depends on May's weather. Larvae can shoot through L4, but if the jet stream jumps south (and some computer forecast models suggest a very cold spell here next weekend) then larval development will slow right down. 

It's too early to call, so watch this space. Last year my prediction for the start of the flight season at Knepp, made in late May, was 24 hours out...

What I can say is that larvae have come through the winter and early spring periods in good numbers. Winter predation was Low-Moderate and early spring losses were officially Low. That's good. This year could see another strong emergence,

Here's one of yesterday's early-L4 larvae -

And here's a larva changing from L3 to L4 - 

Last week, in Heddon Valley on the N Devon coast, we found a fully-grown Dark-green Fritillary larva, and High Brown larvae in L5 (out of 6 instars). At that rate, DGF is likely to appear there around May 20th and HBF around May 27th. And yesterday, I had a half-grown Silver-washed Fritillary larva crawling up my trouser leg...  Here's adippe -

Email me if you want to be included on the People of Purple Persuasion's WhatsApp group (matthew@matthew-oates.co.uk). This is the Inner Sanctum of Purple Affairs...  

Different Asian Cousins

Truly wonderful colours of the first L4 Hestina persimilis larvae. Feeding on Celtis sinensis. Not 'purple' in the truest sense I know, but still some wonderful Apaturinae larvae that many may not have previously seen.

Kicking Off

Minus 5C here last night, but pleased to take this silhouette photo of one of my captive larvae this morning. He's started to feed - 

In Departures Lounge

Purple Emperor larvae are now all out of hibernation. Most are stuck in Departures lounge - waiting for the sallows to stop flowering and come into leaf, so they can feed.  Like this one, taken today in Savernake -

In Savernake, two out of nine have started to feed, one by 'jumping the gun' and biting into a loosening bud -

However, one wild one has desiccated - withered up and died - and one of my captive ones too. I'm not sure what causes this: inadequate autumn diet and excessive late winter / early spring warmth are the two strongest candidates. One of the big butterfly breeders, who raises hundreds of Emperors, thinks it's due to strong drying winds. Two desiccated larvae (and two healthy ones) were found at Knepp last week.

Looks like the weather's turning cold again, so larvae could get seriously stuck in Departures - I've known them to perish there...

Waking Up!

Purple Emperor larvae are just starting to waken from hibernation. I checked my ten surviving wild larvae in Savernake Forest yesterday. Nine were still abed, though greening up strongly. One had just woken up and had a little feed on an unfurling leaf bud (the earliest wild feed I've recorded). He was lucky to find a leaf, most sallows are still bare of leaves, though flowering nicely.

So far, the winter mortality rate is about 33%, which is in the Light to Moderate category. That's good considering that tit numbers appear high. Maybe the tits have had plenty else to eat this winter.

There's a long way to go but 2019 could be another stupendous Emperor season. And at this range an early start is likely. Watch this space...

At home, my captive five are still all conked out, though greening up nicely. None stirred during the late February heat wave, probably because we had light frosts each night. We're in a cold spot, our frogspawn's only just arrived. 

Here's two wild larvae from yesterday -

I am just finishing my labour of love, His Imperial Majesty a natural history of the Purple Emperor butterfly. I am determined to deliver it to Bloomsbury on March 29th, as nothing else is going to get delivered that day...  It's due out in May 2020.

Prospects for 2019

2019 is off to a promising start. Only one of 17 larvae hibernating in Savernake Forest were lost to (assumed) predation during the late November and December period, despite unusually mild weather and high tit numbers. The one that has vanished might have moved, as it was in an unusually warm spot.

Finger's crossed, but it looks as though bird predation may be relatively low this winter, as the blighters have other things to feed on. But the main danger period is late January to the end of February. Hopefully the weather will be cold, snowy and frosty then - and drive the tits out of the forest on to bird feeders in Marlborough, and protect the hibernating larvae.   

Here's are couple of larvae sleeping through the winter -

Meanwhile, I'm beavering away at my opus major His Imperial Majesty, a natural history of the Purple Emperor butterfly. I've got to finish it by the end of March. It's being published by Bloomsbury in May 2020. Watch this space...

The Sallow Tree

Many thanks to Bill Seager of the Fermyn Light Horse for sending me a copy of the essay 'The Sallow Tree' by Nigel Wykes, from 'The pursuit of Moths and Butterflies' (1957, Ed. Patrick Matthews).

A great read and well worth tracking down.