Invasion of Y

Silver Y moth, Autographa gamma

It is about a month since I encountered my first Silver Y moth (Autographa gamma) of the year on the south coast of Ireland. Fluttering with an almost comical gracelessness among the cliff top vegetation, its movements belied the remarkable journey it had just completed. A. gamma is a summer migrant to Ireland, coming from southern Europe, North Africa and even the Middle East to escape the harsh summers there. Offspring produced here will return south in the autumn, a fact made possible by phenotypic variation from their parents. Moths found at higher latitudes (over the range 34- 53°N) have longer pre-reproductive periods, making long migrations back south possible (1).

References:

1. Hill and Gatehouse, 1993. Ecological Entomology 18 pp. 39–46