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Calling all western monarch and milkweed observers!

By candace fallon on 3. October 2017
candace fallon

Fall is here, which means the days are getting shorter, the nights are getting cooler, and monarchs from across the country are moving from summer breeding grounds back to their overwintering sites in California and Mexico. If you live in the West and have photos of monarchs and milkweed, we encourage you to post your observations using the Western Monarch Milkweed Mapper!

Since launching the Mapper at the beginning of the year, over 660 of you have registered on the site and have submitted 450 new records! In 2017 alone, you reported having spent 8,741 minutes observing monarchs and milkweeds in the field—that is almost 146 hours! Check out the map and table below to get a sense of what has been reported for 2017 so far. Can you help us fill in some of the gaps?


wmmm graph


Why your observations matter

Our database houses over 41,000 monarch and milkweed species records, and yet the vast majority of those records are historic or have limited location accuracy, especially if they were collected prior to the widespread use of GPS devices and smart phones. Historic records tell us that a species existed at a certain place and point in time, but without current observations, we can’t have a clear understanding of what is happening now. This is where you come in – by providing highly accurate, present-day data! By submitting your observations with photos and habitat notes, we can better understand where monarchs and milkweeds now occur.

Citizen scientists continue to play a huge role in informing science and furthering conservation efforts. One example of how important citizen science data can be for conservation can be found in the case of the rusty patched bumble bee, which received protection under the endangered species act in part because of citizen science data that helped to demonstrate the disappearance of the species from its historic range.

Another example of the importance of citizen science data can be found in a study recently published in the journal Biological Conservation, which documents severe declines in monarch overwintering populations in California.


wmmm map 2017
A map showing observations to date for 2017. We need more dots!


How your observations help monarchs

All of the Western Monarch Milkweed Mapper data are available through our website for anyone to download and explore. In addition, Xerces and our partners are using the data to better understand what milkweed species monarchs use, the locations of important breeding sites, monarch and milkweed phenologies, and potential threats to their persistence. In addition, highly accurate data points are being used to develop habitat suitability models, and land managers are combining your data with agency survey efforts to inform State Wildlife Action Plans.

Don’t live in the West?

There are other ways to get involved! Check out our list of monarch citizen science projects from across the country. Fall is also a great time to plant monarch and pollinator gardens in many parts of the country. Check out our regional monarch nectar plant guides to get some inspiration.


Your Support Makes a Difference!

Xerces’ conservation work is powered by our donors. Your tax-deductible donation will help us to protect the life that sustains us.