Thanks Wurzel. Whirr of yellow duly recorded, but the cold has returned here and I've seen just one comma since then!
You can't spend too much time with caterpillars, Benjamin.

It was a shame about missing that one. I had examined very, very closely where I held the twig, so as not to crush one of these tiny creatures unintentionally, but believed at the time the caterpillar had hatched the night before and was probably in a flower.
My third hibernating cat began nibbling at his egg-case on 3rd March. I didn't get any decent pictures, but these show the idea:
On 4th March he was still merely sampling the air:
None of the elm flowers on his twig have opened. Does he know this? Is the preparatory opening a way of sniffing the state of his immediate environment?
Today he was still inside but the hole was bigger:
This particular egg is not easily accessible without the risk of breaking twigs, so I can't get good pictures. But I blew up that last shot to show what I think is the caterpillar in the opening:
On the river, the solitary ruff that has spent the last three winters here was feeding avidly, building up strength for his forthcoming nuptials:
The snows brought in plenty of redwing but I was too busy skiing to photograph them. Here's one in the water meadows along the Deben:
Guy