It is believed to be thought that butterflies, or witches that took the shape of the butterfly, to steal milk and butter. Slower butterflies probably fly around 5 mph. Some butterfly species do migrate. This is a relatively new discovery among butterlfies and moths. Most butterflies migrate in one direction, unlike birds who migrate with warm weather.
Butterflies move to a new location and remain there throughout their short life span.
Perhaps they migrate to avoid overpopulation, to find a new home when forced out by development, or deforestation, or even due to temperature changes. There are several reasons for migration, but none is known for sure. A few species are able to survive the winter in any stage of their life cycle by hibernating. During this time the insect goes into a period of inactivity. The body functions slow down so the insect does not need to eat.