Is the monarch migration tracked by placing transmitters on the migrating adults?

The tracking of monarch movement across the country has been done by placing ‘tags’ or stickers marked with a unique 6-character identification code and the name and contact information of the organization the tag belongs to. When a monarch is captured or seen passing through an area the ID code and other information are recorded and submitted to the organization who conducted the tagging. Find out more about tagging programs here.

In September 2023, Cape May Point Science Center and Cellular Tracking Technologies deployed the first ever solar-powered coded digital radio tags on monarchs this week in Cape May Point, NJ. These tags weigh 0.06g and have no battery, so as long as they have sun on them, they will transmit their unique ID once per second. Since they operate on the same frequency as Bluetooth, they can be detected by any smart device running the Project Monarch Science app (with a ~100-200m range from cellphone to tag). The free Project Monarch Science app means YOU can download data and YOU can be a part of the research, logging your sightings and contributing to community science!

The app is available in both iOS and Android app stores:

Project Monarch Science- iOS
Project Monarch Science- Android