Western Monarch Count

The Western Monarch Count (WMC) is an annual effort of volunteer community scientists to collect data on the status of the western monarch population during the overwintering season, which occurs from approximately October through March. The height of this volunteer effort occurs during the Western Monarch Thanksgiving Count, a three week monitoring period in late November/early December, and during the New Year’s Count, a two week monitoring period in late December/early January.

Thanks to the extraordinary effort of a cadre of volunteers, we now have more than 25 years of data demonstrating that monarchs have undergone a dramatic decline estimated more than 95% in the western U.S. since the 1980s. The project is currently managed by the Xerces Society for Invertebrate Conservation and Mia Monroe.