A few late-season species of butterflies like the Mourning Cloak may hibernate over winter and re-emerge in spring, surviving up to 10 months. Similarly, fall broods of Monarchs may live 8 to 9 months migrating to Mexico and portions of the southern California coast to over-winter.
However, for many butterflies, their lifespan can be as short as 14 days. Fortunately, most species produce several broods over summer so it seems they are always around.