Join the 2019 International Monarch Monitoring Blitz

The 3rd Annual International Monarch Monitoring Blitz is happening in Canada, Mexico and the United States from 27 July to 4 August 2019.

For one week, the Blitz invites people across North America to go out to gardens, parks and green areas and monitor milkweed plants for monarch eggs, caterpillars, chrysalises and butterflies. This information will help researchers identify priority areas for monarch conservation actions.

You can help by spreading the word, hosting a monitoring event, or monitoring yourself during this time!

To take part in the Blitz, simply observe milkweed and monarchs, and report your observations. Record the location and area where you monitored, the number of milkweed plants observed, and the number and life stage of monarchs counted (even if there are no monarchs!).

In Canada, report observations to Mission Monarch. If you are east of the Rocky Mountains in the United States report to Monarch Larva Monitoring Project, and if you are west of the Rocky Mountains report to Western Monarch and Milkweed Mapper. In Mexico, you can report to Naturalista or use the Red Monarca app. You can also share about and follow the Blitz on social media using the hashtag #MonarchBlitz.

Regular observations at your MLMP site will also contribute to the Blitz. You do not need to enter weekly site monitoring data in both places. However, we encourage you to find some additional milkweed outside your site to monitor this week using the MLMP Blitz data entry form!

If you want to participate in or host an event, you can find or register one on SciStarter! Just make sure to select ‘International Monarch Monitoring Blitz’ in the ‘What Type of Event’ section.

The Blitz is an initiative of the Trinational Monarch Conservation Science Partnership, created through the Commission for Environmental Cooperation (CEC). Through the Blitz, scientists from the Insectarium/Montréal Space for LifeEnvironment and Climate Change Canada (ECCC), Monarch Joint Venture, the US Fish and Wildlife Service, the Xerces Society for Invertebrate Conservation, and Mexico’s Comisión Nacional de Áreas Naturales Protegidas(Conanp) are asking the public to help them understand monarch and milkweed distribution throughout North America. Data gathered during the Blitz will be uploaded to the Trinational Monarch Knowledge Network, where they will be accessible for anyone for consultation and download.


  • 486 participants across Canada, Mexico, and the United States
  • 1,323 records
  • 53,588 milkweed plants monitored
  • 13,796 monarchs observed
  • 6,905 eggs
  • 4,900 caterpillars
  • 470 chrysalises
  • 1,521 butterflies

For more information, contact André-Philippe Drapeau Picard, Blitz Coordinator, Insectarium/Montréal Space for Life at [email protected].