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A scientific paper, Status of Danaus plexippus in Arizona, that reports the findings of the first ten years of the Southwest Monarch Study has been published in the Journal of the Lepidopterists' Society. You can download it here.

You can also download a pdf summary of the Arizona paper Top Ten Findings of Status of Danaus plexippus in Arizona.pdf

A report entitled Monarch Butterfly (Danaus Plexippus) in New Mexico and a Proposed Framework for its Conservation is now available here..

Visit /SouthwestMonarchStudy for up to the minute monarch news!

The Southwest Monarch Study is researching the migration and breeding patterns of monarch butterflies in Arizona and the SouthWestern United States. It was once believed that monarch butterflies East of the Rocky Mountains flew to the mountains near Mexico City for the winter and monarchs West of the Rockies flew to the coast of California. Through Fall tagging in the Southwest (Arizona, Nevada, New Mexico, California deserts, Utah and Western Colorado), we have learned that this is not always the case.

There is much more to learn about the wild monarch migration throughout the Southwestern states. If you love monarch butterflies, consider joining our study.

Our Mission:

  1. To identify and describe the migration and breeding patterns of Monarch Butterflies (Danaus plexippus) in the Western United States.
  2. To monitor and encourage Monarch Butterfly conservation.
  3. To provide a meaningful research project for citizen scientists of all ages.

How do we do this?

  1. We tag Monarch Butterflies during their Fall migration from August through November. We also tag them while they are overwintering to track their movement between sites.
    See how to tag a Monarch. Click here
  2. We monitor milkweed populations throughout the West. Why is milkweed important? Click here
  3. We look for habitats that attract Monarch Butterflies.
  4. We actively support the North American Monarch Conservation Plan (NAMCP).
  5. We encourage the development of monarch habitats and Monarch Waystations.
  6. We provide educational programs to raise monarch awareness.

What Have We Learned So Far?

Over 400 Citizen Scientists have tagged monarchs for the Southwest Monarch Study. Since 2004, they have tagged thousands of monarch butterflies throughout the Southwest. Through recoveries, we now know that some of these monarchs flew to Mexico, and others to the coast of California (a recovery is a tagged monarch reported in a distant location) We have discovered monarch breeding habitats around the state and are also learning about monarchs that spend the winter in Arizona.

Through analysis of tagging and recovery data, we are also uncovering some fascinating patterns about weather, especially wind, and how it affects the monarch migration.

If a monarch you tagged is sighted in another location we will always contact you.

Look at our sample map. The dark lines represent recoveries in the 2016-2017 season. The light lines represent earlier recoveries.

Who can participate?

Everyone! All ages can learn to tag monarchs.

We are very excited by these recoveries, but there is so much more to learn. Join a tagging trip or tag on your own. No effort is too small—we never know who will discover a new piece in the monarch puzzle. How to tag? Take a few moments to read this link. Come and join us in some of the most beautiful places in the southwestern United States, have fun, and contribute to the understanding of one of the world’s most spectacular natural phenomena, the monarch migration.

If you are interested in joining this exciting research, or would like more information about our recoveries, email:


We Are Now a Nonprofit Organization!

You asked, we listened. Through your encouragement, We are now a federal 501(c)(3) non-profit organization. Your donation helps us purchase tags and print educational brochures as well as offer milkweed seasonally. We are grateful for your financial support of monarch conservation in the southwest. Donations are now tax deductible.

Data Access Policy
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