Visited surviving wild larvae on Saturday. One had died - shrivelled up. A week ago it had looked fine and seemed poised to start feeding.
Most have started to feed, though four of them rather jumped the gun and had bitten into leaf buds that had yet to start unfurling, though three are feeding properly on baby leaves. Three have moved short distances (10-25cm). Five are still lying in waiting, for their chosen leaf buds to start unfurling. There's a problem here for them, as they seem to choose leaf buds at random, rather that pick early developers. For example, two aligned themselves next to dead buds, which begs the question of whether they too will desiccate and die. I fear for them... .
In captivity, one late larva woke up on Saturday (>2 weeks after the others) and immediately started to feed. These larvae are all on non-flowering bushes, which came into leaf much earlier than trees in the wild (which flower before leafing). This means they have a great advantage in that they do not have to wait, post hibernation, for leaf buds to open. Yet the females do not select early-leafing trees in the wild.
I have, though, lost one more captive larva to desiccation (and three all told). This seems to be a problem familiar to those who breed iris. But does anyone have a theory as to what causes it? (I've never breed the species in any numbers, so my sample size has always been too small). It may be due to larvae simply running out of fuel prior to beginning to feed properly, in which case selecting early-leafing trees / branches would be a distinct advantage. Ideas please?