City Nature Challenge: 2026
We are thrilled to announce that the SDSU Biodiversity Museum is co-organizing San Diego County’s 2026 City Nature Challenge for the third year with the San Diego Natural History Museum and the UC San Diego Natural Reserve System.
The 2026 City Nature Challenge is a 4-day, worldwide collaboration to get people observing the natural world. We’re using the free iNaturalist app to make wildlife observations made in San Diego County between April 24 and April 27, 2026.
It’s easy to participate! All wild plants, animals, and fungi count, even non-native species. On the iNaturalist 2026 San Diego County City Nature Challenge Project Page, your observations will directly contribute to science.
The 2026 San Diego County City Nature Challenge Portal has all the information you need to know about how to participate, including the many local events that you can sign up for.
The Biodiversity Museum, the Love Library, and the Green Team also have some events lined up during Citizen Science Month in April, where you can join us to support the City Nature Challenge.
Citizen Science Month: April, 2026
April 15, 2026: Wednesday
All are welcome to the free April 15 webinar, Upping Your Game With Better iNaturalist Observations and Identifications for the City Nature Challenge, where there will be something to learn for everyone.
Register for Zoom Webinar
April 26, 2026: Sunday
You can also join SDSU reptile experts for a fun morning of exploring reptiles, amphibians, and other wildlife on April 26 at Florida Canyon in Balboa Park.
View Flyer (Google Drive PDF)
April 9, 16, 23, 30, 2026: Thursdays
And at the SDSU Farmer’s Market most Thursdays in April, you can learn more about the City Nature Challenge, how to use iNaturalist, and other citizen science opportunities.
Learn More About These Opportunities
The SDSU Biodiversity Museum has a long history of local biodiversity research, and a particularly rich history of collaboration with researchers at The Nat. The Biodiversity Museum’s active role in organizing the CNC continues this tradition and aligns with our current efforts to be more accessible and connected to the community.
