You never know what might be lurking under a piece of bark on a dead tree but I certainly didn’t expect this little guy, especially in the middle of winter. It’s the caterpillar of the Large Yellow Underwing moth (Noctua pronuba) and, as well as being one of Britain’s most common moths, it can also be found throughout Europe and the Middle East, in central Asia and in North America. This moth also migrates so often arrives in southern Britain in huge numbers.

Though the moth is a harmless nectar-feeder, the caterpillar is a ‘cutworm’, a nasty critter that chews through the base of herbaceous plants, both in the garden and on the farm, causing the plants to die. Though I would have expected it to overwinter as a pupa, it seems these minibeasts usually overwinter in their final caterpillar stage and, in mild weather, even emerge to continue feeding. This little guy certainly had a cosy spot for himself under the tree bark … until I came along.

Big thanks to Steve Ogden at Wildlife Insight, who very kindly identified this caterpillar for me. Check out his most excellent website on British moths and butterflies, birds and things to see when watching the sea.