Western Monarch Milkweed Mapper

This project is part of a collaborative effort to map and better understand monarch butterflies and their host plants across the Western U.S. Data compiled through this project will improve our understanding of the distribution and phenology of monarchs and milkweeds, identify important breeding areas, and help us better understand monarch conservation needs. Some of the key research questions that these data will help us answer include:

Where are different milkweed species growing in the West?
Where are monarchs occurring in the West?
Where are monarchs breeding in the West?
When is milkweed emerging and senescing (dying back) in the West?
How does milkweed phenology (life cycle) differ by species?
When is monarch breeding occurring in specific areas/regions of the West?
What types of habitats are different milkweed species associated with?