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Online—Western United States
Ongoing; priority season is early spring

The Western Monarch Milkweed Mapper 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. All you need to do take photos of milkweed and monarchs, upload your photos, and submit! You have three options for submitting: using the iNaturalist app (iOS and Android), uploading to, or using the Monarch SOS app (iOS only).