Greening Up!

Emperor larvae are starting to green up: changing their dull winter coats for the green of the spring, like this (yesterday, in Savernake) -

We checked 11 hibernating larvae in Savernake yesterday. Incredibly, only one out of the original sample of 12 has been lost to bird predation this winter (fingers crossed...). In most winters there, bird predation (titmice mainly) is in the 50-75% range! (Sample size is a problem, obviously).  

I've hardly seen any titmice in Savernake all winter...  When tits are down, Emperors go up...

However, we have lost two larvae in Savernake since mid-Feb, to shrivelling. Like this -

I suspect that this one has had its innards sucked out by a predatory bug, but it may be a virus or diet deficiency - very hard to tell. The second shrivelled one was 5m up, found by Dangle Leaf and spotted & monitored through binoculars - so never seen close up. 

Shieldbugs and the Tree Damsel Bug seem to be appearing earlier and earlier in modern mild winters (though there's no baseline here, no one's been studying them on sallows...). 

In captivity, quite a few larvae simply shrivel up in late winter. We don't know why (?? inadequately fed the previous autumn, ?? run out of fuel in the tank).

Soon, very soon, larvae which have been wintering in forks and scars will move up to swelling buds. A run of cold nights has prevented this happening already.

Also, back in the Cotswolds, in the wooded valley near Daneway Banks, we found a new larva - only he's missing half of his left 'horn', presumably bitten off by some invertebrate predator. I followed one which had its right horn missing during the 2017-18 winter, named 'Stumpy': it got through the winter, fed nicely in April, changed to L4 but promptly died. So, finger's crossed for this one (also called Stumpy) -

At this range, larvae are likely to start feeding in early April.