Community science draws upon data collected by community members trained to observe and create a record of their observations. Aggregating the observations of community observers allows researchers to collect more data more quickly than would be possible using more conventional methods. It's also a great opportunity for participants to learn more about species that interest them.

Community science draws on a wide variety of tools for observing and recording information. The most frequently used tool for reporting observations of monarchs is the application iNaturalist. On iNaturalist, when observers see an organism of interest, they take a photo which is then stamped with the time and location as well as an automated species identification. All the observations collected by observers are aggregated by the app and can be accessed by analysts.

Community science efforts such as the Western Monarch Count address important questions about the distribution of monarchs and milkweed across the western US. For the Western Monarch Count, the Xerces society has trained hundreds volunteers to seek and count monarch butterflies at their overwintering sites. The data they have collected for over 25 years is used by scientists, land managers, media, and educational institutions for documenting population trends. 

In recent years, other projects have included documentation of early spring dispersal patterns (Western Monarch Mystery Challenge) as well as identification of the maximum breeding population size and distribution in mid-summer (International Monarch Monitoring Blitz).  The Monarch Larva Monitoring Project tracks monarch eggs, larvae, and milkweed throughout North America. Local efforts such as those of the conducted by the Pollinator Posse document the role that home gardens can play in monarch recovery.