Act locally, connect globally on behalf of nature everywhere!
Make a difference for your local biodiversity, connect with nature and show the world your community pride — it’s as easy as taking a photo. Put your community’s biodiversity on the map during the 2021 City Nature Challenge (CNC).
Tracking biodiversity around the world is the core activity of the City Nature Challenge (CNC), a friendly, international competition that encourages people to find and document all the plants and wildlife they can find in their city. Using the iNaturalist platform, CNC host cities compete against each other to see which city can make the most observations of nature, find the most species, and engage the most people in this bio-blitz style event. Invented by citizen staff at the Natural History Museum of Los Angeles County and California Academy of Sciences, City Nature Challenge has continued to attract greater participation every year. The CNC has become the largest biodiversity tracking event in the world, so you don’t want to miss out. Last year 244 cities from around the world took part, tracking nearly 1 million observations in just four days (including over 1,300 rare and endangered species). All this happened in the midst of the COVID-19 pandemic, when many events were cancelled or scaled back, so imagine what 2021 will look like.