The monarch butterfly is one of the most well-known and charismatic butterflies in the U.S. However, the monarch population has declined by over 80% in recent years. The monarch migrates to parts of Mexico and California. In the forests of Mexico, deforestation and severe weather have negatively impacted the monarch population, contributing to its decline. Monarchs are also losing their larval food source: milkweed. Native milkweed is being cut down for farming or sprayed with pesticides.