2025 City Nature Challenge starts April 25!
Once again, we are gearing up for the Denver-Boulder City Nature Challenge—part of a global competition among cities to document biodiversity using iNaturalist, a community science platform.
The City Nature Challenge (CNC) is an incredible way to foster connections within the local community to nature, improve trust in science, and contribute to our scientific understanding of our local flora and fauna! This year is the 10th anniversary!
Join the international City Nature Challenge (CNC) event and become community scientists in the greater Denver-Boulder Metro region! This annual event motivates people around the world to take observations of the natural world using the iNaturalist app. Last year, more than 83,000 people participated and made 2.5 million biodiversity observations worldwide.
This event takes place in two parts
The City Nature Challenge consists of two phases – the Observation Phase – where community scientists use the iNaturalist smartphone app to record observations of nature in their city, and the Identification Phase where nature enthusiasts and experts work to link species identifications to the observations.
April 25 to 28: Make observations of wild plants, fungi, animals, insects, etc by taking images with your smart phone or camera
April 29 to May 4: Upload your observations and identify on iNaturalist.
Anyone, anywhere, with a smartphone (or a camera and internet access) can participate in this community science project! The organizers of the global City Nature Challenge have amazing tools on their website that you can use to help spread the word including an educational toolkit, stats from previous events, and information on how these observations impact scientific research: https://citynaturechallenge.org/
Our planning committee partners this year include Denver Botanic Gardens, Denver Parks and Rec, Colorado Open Lands, Longmont Open Space Natural Resources, The Nature Conservancy, High Line Canal Conservancy, and Denver Audubon.