Q: In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.
The western population overwinters in various coastal sites in central and southern California, United States, notably in Pacific Grove, Santa Cruz, and Grover Beach. Western monarchs also overwinter in Baja, California's central valley, and the Sierra Nevada foothills.
A:
where do monarch butterflies migrate to in california