DescriptionNote: For current information about safety/security issues in and around Angangueo (including the El Rosario Monarch Butterfly Sanctuary) as well as the state of Michoacán, refer to the U.S. State Department website (travel.state.gov).
Angangueo (ahn-gahn-GEH-oh), which sits in a canyon carved by the Río Puerco, was a pueblo inhabited by Tarascan Indians long before the arrival of the Spanish. The name means “mouth of the cave.” Towering above are the 10,000-foot peaks of Cerro de Guadalupe, El Campanario and Cerro de la Gotera.
Angangueo's heyday was in the early 20th century, when it was a mining center. Today this hamlet, dominated by two imposing Catholic churches facing each other across the main plaza, survives as a tourist departure point for trips to the surrounding monarch butterfly sanctuaries, most of them in the state of Michoacán.
Every winter the generation of monarchs that have spent the spring and summer in Canada and the United States east of the Rockies arrive in this mountainous, forested region of Mexico as part of their remarkable migratory life cycle. Scientists do not know for sure what inner navigational system guides the insects into making this 2,500-mile journey, although one possible explanation is that more than half of North America's species of milkweed—the caterpillars' food source—are native to Mexico, indicating that the urge to migrate is passed along genetically.
After reaching their wintering grounds the monarchs hibernate, forming enormous colonies that completely cloak the tall pines and firs. In a semi-dormant state they burn almost no energy, but begin to grow more active as the weather warms, preparing for the northward migration in the spring. Several generations hatch along the way, thus continuing the monarch's life cycle for another year.
The monarch has a remarkable ability to survive decimating losses; in the winter of 2002, heavy rainstorms and freezing winter weather killed millions and millions of butterflies. However, both scientists and environmentalists worry that herbicide use in the United States and Canada, which kills milkweed plants, as well as illegal Mexican logging operations that destroy the butterflies' sanctuaries will have a devastating long-term effect on their numbers.
Things to SeeEl Rosario Monarch Butterfly Sanctuary