Developing new tastes

We had a gloriously sunny day for our first day of fieldwork at Conington. The grassland was incredibly short, thanks to the extreme lack of rain this spring, and many of the diminutive spring-annuals were even smaller than usual, making them hard to see! 

Orange-tip butterflies were quite frequent, particularly round the more sheltered margins of the site. The larvae feed on members of the Brassicaceae, but their two favoured species, Cuckooflower and Garlic Mustard do not grow there. They seem to have got round this by utilising the very large population of Hoary Cress, a non-native species from western Asia and south-east Europe, that's become established in the UK and many other parts of the world. This female is ovipositing near the top of the plant. Although Orange-tips are known to use other members of the Brassicaceae, I've not been able to find any reference to them using Hoary Cress. 

The extra shows a pair of Orange-tips about to mate - a flighty and flirtation dance preludes consummation.