Western Monarch Milkweed Mapper

During the spring and summer, monarchs breed across the continental United States and parts of Southern Canada, and yet less is known about where and when monarchs breed in Western North America compared to Eastern North America. The Xerces Society and others are working to change this situation, and we could use your help!

Check out the new platform for accessing and contributing milkweed and monarch observations in the West:

Western Monarch Milkweed Mapper

 The data collected from these efforts is being used to help the many agencies and organizations engaged in monarch conservation. This includes understanding where and when monarchs breed, as well as planning where planting milkweed and nectar plants would be most effective. The data has also been used to develop habitat suitability models for milkweeds and monarchs through our partnership with the Pacific Region of the U.S. Fish and Wildlife Service (USFWS) with a new iteration of the model underway in early 2017. The more data collected, the more accurate this model will be to help identify areas where milkweed plantings and monarchs will flourish. Thanks for supporting monarch conservation! Contact monarchs@xerces.org with any questions.


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Plant Milkweed Seed!

Milkweeds support monarch butterflies, native bees, honey bees, and other beneficial insects. Search for sources of milkweed seed now!

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Pollinator Conservation Resource Center

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Monarch Conservation News
  • Pollinator Conservation Program Digest – December 2018

  • Early Thanksgiving Counts Show a Critically Low Monarch Population in California

  • Western Monarch Numbers Expected to Be Low this Year

  • The Striking Beauty of Oklahoma’s Butterflies

  • Keep Monarchs Wild!

  • Newly released monarch overwintering site management plan provides blueprint for protecting and managing monarch groves

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    Following news of the dramatic decline in monarch numbers, some people are rearing large numbers of monarchs in backyard operations or obtaining them from commercial breeders or other organizations and releasing them with the goal of supplementing local populations. But are such efforts doing more harm than good? Click here to read more