CITY NATURE CHALLENGE

iNaturalist CITY NATURE CHALLENGE: April 24–27

The City Nature Challenge (CNC) is an annual (2026 is the 11th year!) four-day event where people around the world use iNaturalist to document the plants, animals, fungi, and other wildlife living in their cities an neighborhoods. The CNC aims to document nature and help fight biodiversity loss.

The CNC runs in two phases: April 24 – 27 is the observation period and April 28 – May 10 is the identification period. Both are important! Results are revealed on May 13: we find out how many species were observed by how many participants!

Our efforts make a difference. Every observation becomes real biodiversity data, used by researchers, land managers, and policymakers to understand and protect nature worldwide.

The CNC is organized by the Community Science teams at the California Academy of Sciences and the Natural History Museum of Los Angeles County, with support from iNaturalist, and local organizers in every participating city (including our own Woodland Park Zoo!)

Learn more at CityNatureChallenge.org or zoo.org/conservation/naturechallenge.

How to Participate

  • Log in to your iNaturalist account
  • Join the “Seattle-Tacoma Metro Area” group
  • Get outside and observe nature! 
    This means: From April 24 to 27, using the iNaturalist app, take photos or record sounds of nature where you live. Look for WILD plants, animals, fungi, etc. (Wild means it was not put there by people and is not being taken care of by people.) Take a close look at the plants around you. Are there any insects or spiders on them? How many different types of birds can you find? Put on your nature eyes and see your neighborhood in a whole new way. 
Citizen scientists record city nature sightings using the iNaturalist app. Photo courtesy iNaturalist.


Pictured: Citizen scientists record city nature sightings using the iNaturalist app.
Photo courtesy iNaturalist.

In 2025, 102,900 people in 669 cities uploaded more than 3.3 million observations of nature to iNaturalist in the four days of the City Nature Challenge. In Seattle, 1,233 observers logged more than 19,628 observations of 2,138 species. Wow!

What will we find this year?

Resources

Our Resources page includes a looooong list of links to all sorts of information about citizen science opportunities, ecological horticulture, Kirke Park partners, and much more.