City Nature Challenge

Cities around the world will be competing to see who can make the most observations of nature, find the most species, and engage the most people in the 2020 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 their cities. 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 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. In light of the COVID-19 pandemic, the 2021 City Nature Challenge will not be focused on competition; instead we want to embrace the healing power of nature and celebrate tens of thousands of people all around the world, searching for and documenting their local biodiversity, together in this event.


The 2022 City Nature Challenge takes place in 2 parts

April 29 -

May 2

Taking pictures of wild plants and animals.

May 3 -

May 8

Identifying what was found.

Results will be announced on Monday May 9th.

Taking Part is Easy

Find Wildlife

It can be any plant, animal, or any other evidence of life found in your city.

Take a Picture

Take a picture of what you find. Be sure to note the location of the critter or plant.


Share your observations through iNaturalist or your city's chosen platform.

Exploring wildlife during COVID-19

2021 Collective Results


1,270,767 observations


45,300+ species were found


52,777 people participated

View all past winners >