western monarchs


Monarch overwintering in California

Early Thanksgiving Counts Show a Critically Low Monarch Population in California

Published on November 29, 2018

The California overwintering population has been reduced to less than 0.5% of its historical size, and has declined by 86% compared to 2017. While western monarchs are facing unprecedented challenges right now, there is still hope that we can recover the population if we work quickly, strategically, and together.


Monarch flying over showy milkweed, Oregon

Western Monarch Numbers Expected to Be Low this Year

Published on November 15, 2018

You may be asking “What can I do to help the monarch?” Besides protecting habitat, avoiding pesticide use, and planting gardens, another way is to contribute monarch and milkweed data to Xerces-led citizen science efforts—namely, the Western Monarch Thanksgiving Count and the Western Monarch Milkweed Mapper.


Keep Monarchs Wild!

Published on September 11, 2018

Instead of rearing—which is risky and unproven in helping monarchs—we should focus on more effective ways to conserve these glorious wild animals. Our tactics should address the reasons the species is in trouble to begin with. We can do this through taking action to protect natural habitat; to plant native milkweed and flowers; avoid pesticides; support wildlife-friendly, local, and organic agriculture; contribute to research efforts via citizen science; and organize ourselves to push for policy changes.


Managing for Monarchs in the West: A new guide to protecting the monarch butterfly from the Pacific to the Rockies.

Published on April 30, 2018

Monarch butterflies in western North America are in trouble. What was once a huge number of monarchs that converged on overwintering sites in coastal California has dwindled year after year. The number of butterflies has fallen by over 95% since the 1980s, with declines also observed in breeding populations during the spring and summer. With Read more …


Second New Year’s Count Supports Monarchs Movement Between Sites

Published on March 7, 2018

The Xerces Society’s Western Monarch Thanksgiving Count provides a long-running record of the number of monarchs overwintering in California—including the steep decline of recent decades. Volunteers and biologists who take part in the Thanksgiving Count have been invaluable in monitoring the monarch population each fall for over twenty years. Last year, another count was added Read more …


Newly released monarch overwintering site management plan provides blueprint for protecting and managing monarch groves

Published on March 2, 2018

The Xerces Society for Invertebrate Conservation, Groundswell Coastal Ecology, California Department of Parks and Recreation, and the U.S. Fish and Wildlife Service have developed a western monarch butterfly overwintering site management plan that also serves as a template for land managers at other overwintering sites. The Monarch Butterfly Overwintering Site Management Plan for Lighthouse Field Read more …