Monarch butterflies have varying lifespans depending on the generation and whether they migrate. Most adult monarch butterflies living in the summer months live about 2 to 6 weeks. However, the generation that migrates, typically born late in the summer or early fall, can live much longer—about 7 to 8 months. This migratory generation lives through the fall and winter as they travel thousands of miles to overwintering sites in Mexico and then return north in the spring. These longer-lived monarchs delay reproduction until after migration and overwintering, unlike the summer generations that live shorter lives and reproduce quickly.
