Monarch Butterfly

A large, brightly patterned orange and black butterfly of North America, famous for an annual multi-generational migration in which individuals that have never made the journey before fly thousands of kilometers between summer breeding grounds in the United States and Canada and overwintering sites in the oyamel fir forests of central Mexico or, for the smaller western population, coastal California. No single butterfly completes the round trip; the return journey north is made by the descendants of the ones that flew south. Monarch caterpillars feed exclusively on milkweed, whose toxic compounds the caterpillar sequesters in its own body as a defense carried into adulthood, and the loss of milkweed habitat across the migratory corridor is a major driver of the species' decline.