We have entered the dangerous late winter period when hibernating Emperor larvae are most vulnerable to predation. I checked my six wild, unprotected larvae on Jan 16th and was delighted to find that all were again present and correct. No losses to mid-January - wow!
However, today I found that No 1 has vanished. I double-searched for him and shouldn't have missed him, had he moved. It's possible that he's moved and that I overlooked him, as he had previously moved twice after entering full hibernation. He moved a massive 1.5m between Nov 19th and Dec 3rd, and he then moved again between Dec 3rd and Jan 1st, just 15cm. Emperor larvae shouldn't move at all in hibernation, but are doing so increasingly during this era of mild winters (and January was, again, warmer than average in southern England) - one of my three captive larvae at home has moved four times this winter.
Also today, I found that larva No 9 has moved, 11cm, from bud to fork, between Jan 16th and Feb 4th (the temp reached 12C on Jan 28th and was around 10C on four other days in late Jan). He has also shrunk a bit, which is a trifle worrying.
We need a proper spell of hard winter weather to drive the tit flocks out of the forests, and provide some protective frost and snow cover for hibernating larvae.
