I love butterflies. I always have. I love to draw them and paint them and I’m fascinated when I see them flutter by…

I saw these pictures online of monarch butterflies at the Sierra Chincua reserve in Mexico. It is said that this reserve hosts up to one billion butterflies annually as they migrate to warmer climes between every October and March from North America after a 2,500 mile journey.

Pictures by photographer Joel Sartore