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The Monarch Monitoring Blitz Begins Tomorrow!

Jul 28, 2017


  • Community Science

The Monarch Monitoring Blitz starts tomorrow! Grab your hats, sunscreen and clipboards and join fellow citizen scientists for some fresh air and an international monarch monitoring blitz from July 29-August 5th! With enough reports, your information will provide a snapshot that helps scientists understand the range and population size of late summer breeding monarchs across North America.

New to citizen science?  Read Why a monarch monitoring blitz? or veterans can jump right to How to participate? If you're already familiar with the monarch monitoring blitz, help us recruit more citizen scientists by spreading the word on Facebook, Twitter or by sending an email!

Why a monarch monitoring blitz? 

Citizen science programs help us understand how monarch populations change through time.  Unfortunately, data from overwintering monarch colonies indicate that both eastern and western monarch populations have declined by ~70% over the last 20 years.  These overwintering data yield information about survivors of each year’s migration to Mexico or California.  However, because monarchs are widespread throughout North America, it is difficult to accurately capture the size of the breeding population (before they migrate). We’re partnering across Canada, the US and Mexico to engage citizen scientists in gathering data about monarch late summer breeding for one week (July 29th – August 5th). By crowdsourcing data from across the entire range during one small time window, citizen scientists from all three countries will help capture a snapshot of monarch breeding activity prior to peak migration. We encourage you to report your observations wherever you are (where there is milkweed); no matter where you report from, your data will be useful in documenting late summer breeding activity throughout the monarch range! Remember to also report your fall migratory adult sightings to Journey North!

How to participate in the monarch monitoring blitz? 

Participating in the monarch monitoring blitz is easy!  Visit monarch habitat that contains milkweed between July 29th and August 5th, check for monarch eggs, caterpillars, and chrysalises, and report your observations! Eggs and caterpillars can be found on milkweed plants, but chrysalises are rarely observed on milkweed plants.  Eggs, caterpillars and chrysalises are evidence that monarchs are reproducing.  Here is where you should report:

USA: Monarch Larva Monitoring Project (MLMP)

Canada: Mission Monarch

Mexico: Naturalista

Interested in getting more involved in citizen science? We encourage you to explore additional citizen science programs, and report anytime you see monarchs!     


The Monarch Joint Venture is a national partnership of federal and state agencies, non-governmental organizations, and academic programs working together to conserve the monarch butterfly migration. The content in this article does not necessarily reflect the positions of all Monarch Joint Venture partners. Header photo by Wendy Caldwell.