Living in the San Francisco Bay area is a blessing for nature lovers. In close vicinity to one of the most populated areas bustling with technological creativity, there exist wild places allowing us to experience and enjoy nature and its marvels. The winter migration of Monarch butterflies is one such spectacle, part of which we can witness in our backyard, at the Natural Bridges State Park, near the city of Santa Cruz.
Every fall, the Monarch’s by sensing the change in temperature start migrating towards the warmer south. Butterflies east of the Rockies migrate to their sanctuaries in Mexico while the ones on the west come to Santa Cruz and Pacific Grove in California. Arriving by mid-October, they generally stay until March before flying back North. Being cold blooded, the Monarch’s are affected by ambient temperature. Only when the temperatures rise above 55F (13C), they start to fly around and forage for food. To keep warm during cold nights and early morning, the Monarch’s huddle in big groups and hang from Eucalyptus trees. An early morning visit to the preserve with a binocular (recommended) gives an excellent chance to catch them resting in the trees.
Such a big number of dormant butterflies attract predators such as a Stellar’s Jay. But thanks to the poisonous nature of the butterflies, the birds find them distasteful and generally spit them out after giving a try.