SANTA FE, N.M. — If you grew up in New Mexico, you probably remember a time when lots of monarch butterflies wafted through the air in late summer and early fall. These days, they’re a relatively rare sight. Sadly, monarch butterfly populations are under severe stress. They have declined by 85% in the past two decades, prompting the monarch to be considered for protection under the Endangered Species Act.
In Mexican lore, the monarch butterfly holds a mystical power. They were considered the embodiment of heroes and the newly departed dead. The Teotihuacan culture venerated the butterfly in frescos and on palace walls, and Toltec warriors emblazoned them on their breastplates.
It’s easy to understand why. Butterflies are a marvel of natural engineering, transforming from an egg to a caterpillar to the final dramatic emergence from a chrysalis as a fully formed butterfly. Monarchs are particularly impressive as they are the only butterfly known to make a two-way migration, similar to birds. Unlike other butterflies that can overwinter as larvae, pupae or adults, monarchs cannot survive the cold winters in North America. As the days shorten and the nights get colder, the monarchs know it is time to travel south to Mexico or west to California for the winter.
Key to monarchs’ survival and reproduction are milkweed plants. Female monarchs lay their eggs only on milkweed, which the caterpillars need to grow and develop. Milkweed grows across New Mexico and you might even find locally native species in your backyard. Because of the monarch’s dependence on this plant during the breeding season in the spring and summer, protecting it also protects the butterfly.