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City Nature Challenge
City Nature Challenge
​​​​​​​​​​​​​​​​​Great Horned Own

iNaturalist City Nature Cha​​llenge 2019​

Boulder, Denver, Colorado Springs and Fort Collins are taking part in the 2019 City Nature Challenge, an international effort to find and document plants and wildlife in cities across the globe. Cities are competing against each other to see who can make the most observations of nature, who can find the most species, and who can engage the most people.

The City Nature Challenge is organized by the California Academy of Sciences​ and the Natural History Museum of Los Angeles County

How to Participate

2018 City Nature Challenge 2018 City Nature Challenge

​​Visit, download the free iNaturalist app from the AppStore or Google Play​ (includes the CPW State Parks NatureFinder), join the Boulder, Denver, Colorado Springs or Fort Collins project, then get outside and start taking pictures of the nature around you. ​

The main City Nature Challenge will take place in two parts: 

From April 26 through 29, Colorado residents are encouraged to go outside to photograph and identify plants and animals as part of this global competition and help your city win the City Nature Challenge! 

From April 30 - May 5, anyone can help identify the photos of plants and wildlife down to the species level. Only the observations with species-level identification will count toward the total!  ​

Join a more intense "BioBlitz" at a State Park:

You can participate in the City Nature Challenge with others at two "BioBlitzes" in Denver-area state parks! What's a BioBlitz? According to Wikipedia, a BioBlitz is defined as "an intense period of biological surveying in an attempt to record all the living species within a designated area. Groups of scientists, naturalists and volunteers conduct an intensive field study over a continuous time period (e.g., usually 24 hours)."

Although CPW does host 24-hour BioBlitzes, the City Nature Challenge BioBlitz is a shorter version designed to get you outside using the iNaturalist app with others. Come join us!

BioBlitz Dates and Times

Your Participation Helps Colorado's Scientists

By participating, you will not only help your city win the competition, you will also be contributing crucial data about Colorado’s unique biodiversity. Scientists can then use this information to make important decisions about how to protect and improve Colorado’s nature.

The iNaturalist app has been an ongoing part of Colorado Parks and Wildlife’s efforts to engage citizen scientists.​

Learn More About the State Parks NatureFinder

Part of the fun of the City Nature Challenge is the simple joy of learning about the nature that exists right outside your front door. Once you've started identifying what's in your yard, you may get the urge to journey even further! CPW's State Parks Nature​Finder (part of iNaturalist) is perfect for those hoping to learn more about and document the wildlife in Colorado's 41 state parks.

Virtual Guidebooks for the NatureFinder

The Resource Stewardship Program​ at CPW has developed virtual guidebooks for the NatureFi​​nder to help you more easily identify the species found in Colorado's state parks. Check out the plant and animal guides staff have created to help you on your journey. ​​​