Data


The Western Monarch Thanksgiving & New Year’s Counts

The Western Monarch Thanksgiving Count and New Year’s Count are the product of annual monitoring efforts by volunteer citizen scientists to collect data on the status of monarch populations overwintering along the California coast (and a few sites from inland areas). Thanks to the extraordinary efforts of these volunteers, we have over 20 years of data demonstrating that monarchs have undergone a dramatic decline in the western U.S.

The data collected by volunteers are compiled and entered into the Xerces Society’s Western Monarch Overwintering Sites Database which also includes many historic counts and survey efforts. Contact wmtc@xerces.org if you are interested in obtaining a copy of the entire database.

You can download the Thanksgiving and New Year’s for every year by clicking on the PDF or excel links below. The graph of Thanksgiving count totals and monitoring effort is updated each year.

Results from the 2017 Western Monarch Thanksgiving Count are now available!

Western Monarch Thanksgiving Count Data 1997-2017 in pdf and excel.

See our press release regarding the 2017 Western Monarch Thanksgiving Count.

Click Here for a larger version.

 

Results from the 2018 Western Monarch New Year’s Count are now available!

2018 data available in pdf and excel.

2017 data available in pdf and excel.

See our blog regarding the 2018 Western Monarch New Year’s Count.

Monarch abundance at 115 overwintering sites in California counted during both the 2017-2018 Thanksgiving and New Year’s Count efforts.