I just visited Pacific Grove, Calif., known as Butterfly Town USA. At the Monarch Grove Sanctuary, I looked at what appeared to be a grove of eucalyptus trees. As we walked closer, a volunteer with Friends of the Monarchs said they had a telescope set up for viewing. Since all I could see were what I thought were dead leaves of trees, I had an unbelievable surprise when I looked through the scope.
Hundreds of monarch butterflies were hanging from the leaves of the trees. Their wings were folded to conserve heat because the day was cold and damp. Occasionally, a butterfly would open its wings to reveal magnificent orange, black and white patterns.
Each October, monarchs west of the Rockies migrate to the Northern California coast. Their migration from cold locales is triggered by decreasing daylight, directing them to travel up to 2,000 miles to warmer coastal climates. They travel as far as 200 miles a day, at elevations up to 10,000 feet.
The coast provides a perfect microclimate for the monarchs because of its humidity, light, shade, temperature and protection from the wind.
At Pacific Grove, eucalyptus trees bloom in the winter and provide the monarchs with a much-needed nectar source.
One unique factor about the monarch migration is that several generations of butterflies live and die between each migratory flight. Those that come to the coast have never been there before.
Most monarchs live only a few weeks, but those that are autumn-hatched actually live for six to nine months and are responsible for the survival of the species.
They feed on nectar along their migratory path, building up fat reserves that allow them to survive the winter months. After arriving at their wintering sites, they conserve their energy by hanging from the trees during the cool days, waiting for the sun to warm them. They fly only when the temperature rises above 55 degrees. They stay for five months before returning to their summer habitats.
Dwindling habitat and open space, along with increased development, threaten the western monarchs. Eastern monarchs are endangered by deforestation in Mexico.
The Pacific Grove Friends of the Monarchs, through the Pacific Grove Chamber of Commerce and the Natural History Museum, support butterfly conservation efforts. To maintain thriving butterfly populations, people can plant nectar sources including milkweed for the monarchs, minimize the use of herbicides, insecticides and fungicides and support open space and wildlife habitat legislation.
For more information on gardening, contact me, 887-2252 or email@example.com, or your local University of Nevada Cooperative Extension office. Check out many useful horticulture publications at www.unce.unr.edu. "Ask a Master Gardener" by e-mailing firstname.lastname@example.org.
-- JoAnne Skelly is the Carson City/Storey County Extension Educator for University of Nevada Cooperative Extension.