Although we have crashed into winter, with temperatures dropping below 0°C and not rising above 15°C, following a warm spell of weather with temperatures in the 20s, it's the sort of winter everyone can enjoy. The frost has been heavy, but the days clear and sunny, and the late season butterflies are hanging on, nourished by ivy, valerian and African marigolds.
Speaking of marigolds, one of the most common butterflies on the wing at the moment is the Clouded Yellow Colias crocea. Its French name is le Souci (i.e. the Marigold).
Simon took advantage of one of the 'motor drive' type functions on his new camera to take a series of wonderful photos of Clouded Yellows working over some African marigolds up by the chateau on a sunny afternoon a few days ago. He was amazed by how much effort flying takes and what muscular power these butterflies have.
Theoretically, we get 3 species of Clouded Yellow here - Pale Clouded Yellow C. hyale, Berger's Clouded Yellow C. alfacariensis and Clouded Yellow C. crocea. In practice, my experience is that if you see a Clouded Yellow it will almost always be C. crocea.
The 3 species are notoriously difficult to tell apart. There are some subtle differences in wing shapes (virtually impossible to distinguish without having the different species side by side to compare) and all the other features observable with the naked eye concern the patterning on the upper sides of the wings. Unfortunately, this species almost never rests with its wings open, and you can not always be sure of the details if you see them bouncing past you on the wing. Being able to take action shots that freeze the view of the upper sides really helps with identification later.
I find the easiest feature to check is the dark band on the edges of the lower wings. If it is thick and dark rather than petering out into thin scallops or even reduced to a series of spots the butterfly is C. crocea. If the dark margin is weaker, you have one of the other species (and a real headache if you want to get further than that). They pass the winter as caterpillars, coming out to eat various legumes when the weather allows and slowly growing until they can transform into adults in the spring.
PS Souci is actually the French for Pot Marigold Calendula officinalis, not African Marigold Tagetes hybrids. African Marigolds are also known as French Marigolds. Simon was not wearing Marigolds when he took these photos - that would be silly.