Adam, there's no data as such that records the longevity of individual moths; however, adult will live from 1 day to about 4 weeks depending on the species and even longer if they aestivate or hibernate. Most don't live very long at all as they are prey items for many higher orders like bats and birds. The extended flight periods reflect the fact that adults will emerge and die throught that flight period, they don't all emerge at the same time.
Yes, we are seeing foreign invaders, both as genuine immigrants and imported on produce, with some now colonising as the climate warms up. These make up for the ones we have lost. Climate change has much to do with this along with habitat loss and farming practices.
Les Evans-Hill ● 2577d