Hawk Migration Association of North America

Monarch Butterfly
Migration Monitoring

The North American network of monarch butterfly monitoring programs


There’s a long history of counting migrating monarch butterflies at raptor monitoring sites across the continent. Whether intentionally scanning for them, tallying here and there as they drift through your field of view, or trapping and tagging them, hawk watchers have been counting and admiring these migrating beauties for decades. Many sites enjoy keeping daily totals and comparing year to year as their numbers fluctuate. Most hawk watchers comment to some degree on their presence in their non-raptor notes or daily observations in their HawkCount reports. This has resulted in a wealth of information in the HawkCount database about migrating monarch abundance and the routes they favor. If only there were a way to get this information to monarch butterfly biologists. Well, now there is! HMANA is partnering with MonarchNet so that this valuable data collected at hawk watch sites can be used to understand their migration patterns better.


The mission of MonarchNet is to create a central website where everyone can gain access to information about monarch monitoring programs, learn how to access the data, and find tools for data visualization to learn about monarch dynamics throughout North America.

This website serves as a resource for anyone who wants to know about monarch populations (i.e., government officials, researchers, members of the general public, or NGOs). Since the partners represent the most critical monitoring programs that collect monarchs’ data, the collective data represent the most current and comprehensive information on monarch biology. We hope that by linking the data sets, our efforts will foster collaboration between monitoring programs, promote the use of the data to answer scientific questions, increase participation by citizen-scientists in multiple programs, and increase awareness of each monitoring program.

MonarchNet was started in 2009 during a meeting of scientists and monarch butterfly biologists, who proposed a cooperative network of monitoring programs and a central place where the data from such programs would be accessible. This effort is now a reality and a significant step forward for monarch butterfly conservation. MonarchNet is currently a joint project of the North American Butterfly Monitoring Network, led by Leslie Ries, and the Monarch Joint Venture, led by Karen Oberhauser.

How It Will Work

Rather than adding monarch totals in the daily observations notes or comment section for each day, sites now have the opportunity to add unique data fields to their HawkCount account. Sites will enter the numeric total of monarchs counted that day and be asked if all monarchs counted were reported to clarify whether counting effort was constant throughout the day or only for two of the eight-hour count, for example. Monitoring monarchs is, of course, optional, so sites may choose whether or not they’d like to participate and how much they’d like to. Some areas may choose to focus all their effort solely on raptors, while others may make monarch monitoring a priority. We appreciate any level of contribution that works for you!

This data will be shared with MonarchNet better to understand their populations and migration across the continent. HMANA is also currently working with MonarchNet to draw historical observations from HawkCount to access data before 2019.

Get Involved

If you are a hawk watcher currently submitting raptor data to the HawkCount database and would like your site to participate in Monarch Migration Monitoring, please contact Julie Brown at brown@hmana.org or to learn more about MonarchNet, visit www.monarchnet.org.