The 2025 City Nature Challenge is a 4-day, worldwide collaboration to get people observing the natural world through photography—and The Nat and SDSU Biodiversity Museum are coordinating San Diego’s annual participation! We're using the free iNaturalist app and iNaturalist.org website to tally results for observations made in San Diego County. All wild plants and animals count, even non-native species. The City Nature Challenge will take place April 25–28, 2025.
It’s easy! You can go out on your own, join our partners at one of the many special events hosted remotely and around town, or find an event near you. All you have to do is:
And we have plenty of resources to help you along the way.
This county-wide effort is possible because of our dedicated partners. Interested in joining?
Educators—want to incorporate the City Nature Challenge into your curriculum? We've got your back.
Featured above: The critically imperiled western beach tiger beetle (Cicindela latesignata) was spotted by iNaturalist user mhrains as part of the 2022 CNC.
City Nature Challenge exists thanks to its founding organizations, CalAcademy and the Natural History Museum of Los Angeles County, and thanks to support from people like you.