Western Monarch Thanksgiving Count

Check out our new website for more detailed information about the count and how to participate!

The Western Monarch Thanksgiving Count is a yearly effort of volunteer citizen monitors to collect data on the status of monarch populations overwintering along the California coast. Thanks to the extraordinary efforts of a cadre of volunteers, we have over two decades of data demonstrating that monarchs have undergone a dramatic decline in the western U.S. This effort is coordinated by Mia Monroe and the Xerces Society.

Would you like to participate in the Western Monarch Thanksgiving Count? We are looking for volunteers in California who can commit to visiting the same overwintering sites year after year.

Please remember that we are most interested in counts of monarch groves conducted during a three week period centered on Thanksgiving and around New Years day. We also encourage Thanksgiving Count monitors to also fill out a brief, one-page habitat assessment so that we can understand more about what monarchs need and begin to track changes that occur at overwintering sites. You can download survey instructions and data sheets from the Western Monarch Count website.

See our press release regarding the 2015 Western Monarch Thanksgiving Count numbers.


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Program Features
Program Highlights
  • • The Xerces Society has awarded two $3,750 Joan M. DeWind awards for research into lepidoptera conservation
  • Butterfly-a-thon pledges raise $30 per species that Bob Pyle observes for butterfly conservation work
Additional Information
monarch butterflies (Danaus plexippus) by Carly Voight, The Xerces Society