CCS City Nature Challenge

City Nature Challenge


The City Nature Challenge began as a nature-observation competition between the San Francisco Bay Area and Los Angeles County in 2016. Since then, the competition has expanded worldwide, with over 160 cities participating in 2019. Participants use the iNaturalist app to photograph, catalogue and identify observations of wildlife in the area, thus learning from each other and contributing to a global database that scientists all over the world can access and use to help better understand and protect nature.

In 2019, Sacramento took part in the City Nature Challenge for the first time, and we were amazed by its success! Over 500 people participated, logging 9,798 local observations of 1,279 species. Many different collaborators contributed to the success of the CNC Sacramento. In Woodland, CA, educators taught elementary students how to bioblitz, and the California Naturalist Program, along with several research and nature centers, hosted their own bioblitzes.

Based on the amazing turnout last year, we’re aiming for 15,000 observations in 2020. Click here to find out more about this year’s events and opportunities to participate.

Read more about the City Nature Challenge in the posts below, and check back here for upcoming opportunities and information. 


Did Covid-19 make the “City Nature Challenge” less green?

For his capstone project in the Wild Davis course, taught by CCS Faculty Fellow Laci Gerhart, Nicholas Monty explored spatial shifts in City Nature Challenge observation patterns between 2019 and 2020, using remote sensing measurements of relative “greenness.” We’re happy to share his fascinating approach here. Thank you Nicholas!


This Friday: 2020 City Nature Challenge!

     “This year we want to celebrate life where life is challenged.” 
                                                                                                - Jaime González


City Nature Challenge & COVID-19

The global challenge… fought locally

2020’s City Nature Challenge has been modified to keep organizers and participants safe during the COVID-19 pandemic. Rather than the typical competition, this year’s CNC is focusing on collaboration and spending restorative time in nature. You can still document biodiversity safely, although it may require some extra creativity or staying in your home.

The 2020 City Nature Challenge takes place in two parts —

  • April 24 – 27: Taking pictures of wild plants and animals.
  • April 28 – May 3: Identifying what was found.

Engaging Educators in the City Nature Challenge

The Center collaborated with the California Naturalist Program, educators in the Woodland Joint Unified School District, and a variety of local nature centers and reserves to encourage participation in the Sacramento City Nature Challenge. Despite being its first year participating in this global competition (as one of more than 160 cities worldwide), over 500 people in the Sacramento region logged 9,798 observations of over 1,200 unique species using iNaturalist.


City Nature Challenge Comes to Sacramento Region

For the first time ever, the Sacramento Region will be participating in the City Nature Challenge. We will be competing with more than 160 cities all over the world to see who can catalogue the most nature in just 4 days! We think that joining this global effort to discover local biodiversity through citizen science is a great opportunity for the Center, and for the region.  



April 26th 2019- April 29th 2019

The City Nature Challenge began as a nature-observation competition between the San Francisco Bay Area and Los Angeles County in 2016, organized around simple charge: “which city can find the most nature?” Since then, the competition has expanded rapidly, and this year more than 120 cities will participate worldwide!

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