Participate in collecting data on western monarchs and milkweed

The 2016 field season is underway with monarchs pushing into the Pacific Northwest latitudes and milkweed plants emerging. Your participation is needed to make the Western Monarch and Milkweed Habitat Suitability Model Project a success, and to provide the best western-wide habitat models for all agencies, organizations, and individuals interested in conserving the monarchs of the western USA. 

The U.S. Fish and Wildlife Service and the Xerces Society for Invertebrate Conservation are gearing up for a second field season to collect occurrence data on the monarch butterfly and its milkweed host plants. This project encompasses all lands west of the Rocky Mountains (the range of the western monarch), and includes many partnering federal and state agencies, and NGO’s.

The primary objective of this project is to provide high-resolution GIS layers depicting the highest priority areas to conserve and create monarch habitat in the West. This will assist agencies and partners in prioritizing habitat restoration and enhancement projects, identify potential collaborative projects, and effectively using limited habitat restoration funding. The Habitat Suitability Models, including the database generated from this project, are available to all interested agencies and organizations.

Filling in the Gaps

During 2015, most of the initial data collection effort focused on the Pacific Northwest, but the project is now in need of filling substantial data gaps through the entire West. The USFWS, the Xerces Society, and the Monarch Joint Venture have developed several tools for collecting and reporting monarch and milkweed sightings in 2016, including an Excel Workbook, an on-line reporting tool, and an iOS app called Monarch SOS. The link to these tools can be found at: In addition, the USFWS has developed a geodatabase for collecting this data on compatible GPS units.

After the 2015 season, Habitat Suitability Models were run for monarchs and 5 key species of milkweed plants in the West; these models included 25 environmental variables used to determine habitat and climate conditions that may influence these species’ distributions. The upshot of this first season is that significant landscape-level data gaps exist for monarchs and milkweeds in the West, and there is a need for high-resolution distribution data for all species.

Access 2015-16 Monarch/Milkweed Habitat Suitability Model Products

DOI employees

Non-DOI employees

Questions About the Project

If you have questions, need additional information about this project, or are interested in using the geodatabase, please contact: Ashley Taylor, Regional Monarch and Pollinator Conservation Specialist or Joe Engler, U.S. Fish and Wildlife, Region 1 Pollinator Coordinator.


Map of monarch breeding records and milkweed records