Anderson Cooper and the 60 Minutes team documented the annual migration of monarch butterflies, an event that remains one of science's great mysteries. Millions of monarchs begin their trek north from Mexico each spring, where they have spent the winter. The butterflies fly south from the U.S. and Canada each fall, yet they instinctively know the correct path to migrate even though they have never made the long journey themselves.
The expedition to witness this migration was challenging. The 60 Minutes team spent three years planning the story, which was shot in 2025. The window during which butterflies leave their overwintering roosts in Mexico's pine and fir trees is short and heavily dependent on weather conditions. This year, the temperature was uncooperative for days before the team began shooting.
To reach the preserve, the team first rode horses, then hiked, all while carrying camera gear. The journey was arduous, and the team faced the risk of not capturing the butterflies in flight if the weather was not favorable. When they arrived, the weather was cloudy and cold. The fir trees sagged under the weight of the roosting butterflies, and the monarchs' characteristic orange colors were not visible when their wings were closed. Many butterflies lay on the ground, some dead and others too cold to move.
The monarchs roost in patches of fir and pine trees at an elevation of 11,000 feet. Last year, more than 60 million monarch butterflies were found in a four-and-a-half-acre patch of forest. The population in Mexico has declined by 70% in the last 30 years, raising concerns about the future of this remarkable migration.