They fly 2,000 miles to return to their winter home. When the temperature dips below 55, they gather in pulsating clusters, clinging to eucalyptus branches, their feet intertwined. The day warms, and sunlight falls on a cluster. They burst forth, a fluttering orange and black cloud.
Natural Bridges State Beach, just north of Santa Cruz, is the winter home of a colony of thousands of monarch butterflies. They arrive in mid-October and stay until mid-February. Then they leave for an amazing four-generation annual migration.
Newborns set out, heading northeast, laying eggs on milkweed. The initial generation dies, but new caterpillars are born, feed on milkweed, form chrysalises, and emerge as a second generation. They fly over the Sierra Nevada Mountains and repeat the process. Generation three spreads out to the Pacific NW, Southern Canada, and the Western Rockies. When days grow short, generation four, traveling at 5.5 mph, flies the 2,000 miles back to Natural Bridges.
Although Western North American monarchs winter in many sites along the California and Baja coast, Natural Bridges State Beach is California’s only state monarch preserve. Leave the beach, and follow a path that leads to a canyon with a eucalyptus grove, boardwalk, and observation deck. Visitors descend into the grove and speak in hushed tones, feeling they have entered a sacred and magical spot. Monarchs flitter overhead. One may land on your arm.
Herbicides and loss of breeding habitat threaten monarch populations. A 2014 study estimated the Western North American monarchs have declined 50% since 1997. Their eastern cousins, who migrate from north and central U.S. and Southern Canada to Florida and Mexico, have declined 90% since 1995.
Efforts are underway to preserve habitat and to create “Monarch Waystations,” – parks, fields, and home gardens planted with milkweed. Check out your local nursery for milkweed plants or seeds. Plant organic milkweed, and create your own waystation!