CATERPILLARS IN DECEMBER AT SALE GREEN, NEAR DROITWICH

Colin Harrison

Due to a frost-free autumn some nasturtium plants situated in a sunny south facing corner of my house where still growing and flowering in November 2002. On close investigation it was discovered that caterpillars of both the Small White Pieris rapae and the Large White Pieris brassicae where present. A watch was kept on these insects and on1st December at least one caterpillars of each species were still to be found on the leaves of the plant with a further few climbing away up the wall to pupate.

The Millennium Atlas of Butterflies of Britain and Ireland does suggest there can be three broods of these two butterflies and this observation is perhaps an unusually late example of caterpillars from a second brood, or even perhaps of larvae from eggs laid by a third brood. Survival of caterpillars from a third brood to pupation and over-wintering must be unusual.

It would be interesting to hear of any other examples of December larvae of these two Whites

Reference
ASHER, J, et al 2001.The Millennium Atlas of Butterflies in Britain and Ireland. OUP