What is the City Nature Challenge?
Started in 2016 as a competition between San Francisco and Los Angeles, the City Nature Challenge (CNC) has grown into an international event, motivating people around the world to find and document wildlife in and around their cities, using biodiversity recording apps and platforms like iNaturalist. Run by the Community Science teams at the California Academy of Sciences and the Natural History Museum of Los Angeles County, the CNC is an annual four-day global urban bioblitz at the end of April, where cities are in a collaboration-meets-friendly-competition to see not only what can be accomplished when we all work toward a common goal, but also which city can gather the most observations of nature, find the most species, and engage the most people in the event.
The 2024 City Nature Challenge will be April 26 – 29. Last year there were 485 cities across 46 countries who took part! Participating is easy: just use iNaturalist to make and share observations of wild plants and animals in any of the nine Bay Area counties. Be sure to check back here as well for information about City Nature Challenge events happening throughout the Bay Area.
How to Participate
Participating in the City Nature Challenge is easy!
- Download the free iNaturalist app and make an account.
- April 26 - April 29, take photos of WILD plants and animals anywhere in the nine Bay Area Counties (San Francisco, San Mateo, Santa Clara, Alameda, Contra Costa, Solano, Napa, Sonoma, Marin).
- Upload your observations to share with the iNaturalist community. They will automatically be added to our San Francisco Bay Area City Nature Challenge project!
- Learn more as your finds get identified!
Bay Area CNC Events
Join upcoming events for the City Nature Challenge 2024 to learn more our local species, get hands-on help using iNaturalist, and meet other people interested in nature! Click on the links to learn more and to register if needed. All events are in-person unless noted and will be hosted in English unless noted. Be sure to check back as we'll be adding more events!
Special thanks to our partners
From getting the word out to hosting events, the Academy's Bay Area partners make City Nature Challenge the inspiring, empowering, and fun 4-day nature bioblitz that it is—and we are incredibly grateful. Click the links below to learn more about each group.
California Native Plant Society | California Lichen Society | Latino Outdoors | California State Parks: Candlestick Point SRA | Bay Nature | San Francisco Department of the Environment | Nature in the City | Presidio Trust | Golden Gate Audubon Society | California Native Plant Society Yerba Buena Chapter | Sutro Stewards | Golden Gate National Recreation Area | San Mateo County Parks | Sequoia Audubon Society | Bioblitz.club | East Bay Regional Parks | California Center for Natural History | Community for Lake Merritt | Oakland Zoo | Oakland Museum of California | Wholly H2o | One Tam | Marin Municipal Water District | Marin County Parks | Sonoma Ecology Center | Sonoma County Parks | Pepperwood Preserve | Napa County RCD | Saved by Nature | Keep Coyote Creek Beautiful | Santa Clara Valley Audubon Society | Grassroots Ecology
Explore, observe, and document the plants and animals around you—even inside your house!
You don't need to venture too far from home to find exciting and surprising creatures! Download this PDF to get started.
Download this PDF and see if you can find all 25 of these commonly observed Bay Area (plant and animal) neighbors.
Don't have iNat yet? Download the app today and discover how fun (and easy) it is to document biodiversity in your neighborhood.
The work we do utilizes iNaturalist to make biodiversity observations while building community around nature. It's a community-powered website and app that makes it easy to upload and share your observations in the field and to get help from other users with flora and fauna IDs.