Right now Wicklow is swarming with Silver-Ys, muscular moths which migrate from North Africa and southern Europe every summer. Some years they are in small numbers, and some years in large ones, and this year they are in the latter. You will see them flying by night mostly, but individuals are very noticeable by day too, moving from place to place or perching on walls and windows. They come to garden plants by night in hovering swarms which are very impressive.
The moth’s scientific name, Autographa gamma, literally means ‘self-written y’. Both the common and scientific name are due to a silver-coloured ‘y’ marking on each forewing, as you can see clearly in the photo below.
Silver-Y moths are believed to attempt to migrate home in autumn, but some will instead opt to hibernate, and with some success as I have discovered them springing to life in sheds in springtime. It’s difficult to know how long they can live but we do know Painted Lady butterflies not only migrate from North Africa to Ireland, but also can successfully make the return journey in autumn, so the robust Silver-Y should be equally capable of this feat. As with so much in nature, however, it remains to be conclusively proven.