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 2023 City Nature Challenge will be April 28 – May 1. 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.

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