City Nature Challenge

City Nature Challenge

April 26 – May 5

What is the City Nature Challenge?

The City Nature Challenge (CNC) is an international effort to document biodiversity by finding and documenting plants and wildlife across the globe. Cities are encouraging their community members to get outside and document the plants and animals in their region. The CNC is organized by the California Academy of Sciences and the Natural History Museum of Los Angeles County.

General information about the CNC

Further questions? Please email us.

Why should you participate?

There is nature all around us, even in our cities! Knowing what species are here and where they are helps us study and protect them, but the ONLY way to effectively do that is by working together (scientists, land managers, community members, you name it) to find and document nature in our area. By participating in the CNC, not only do you learn more about local nature, but you can also make our urban areas a better place – for you and other species!

When should I participate?

  • Make your observations between Friday, April 26 and Monday, April 29
  • Between April 30 to May 5, help us identify as many observations as possible within the project. 
  • Observations must be uploaded by May 5 to count towards our total observations for the CNC. 
  • Results announced on May 6.

How Can I Participate?

Here’s how you can get involved in the Denver-Boulder Metro area:

Walks, Hikes and Stewardship Events

Denver Parks and Recreation - Education and Wildlife Management


Denver Audubon

  • Nature Talk n' Trek - 17 Mile House Farm Park, Friday, April 26, 9:30-11:30 a.m., 17 Mile Farm House Park Sign up for this hike
  • Kingery Nature Center Bioblitz, Saturday, April 27, noon – 2:30 p.m., Kingery Nature Center Sign up for this hike


High Line Canal Conservancy

  • Waterton Canyon City Nature Challenge Bioblitz, Sunday, April 28, 9-11:30 a.m., Waterton Canyon Sign up for this hike


The Greenway Foundation 

  • Spring South Platte Stewardship Day (a river clean-up event sponsored by The Nature Conservancy), Saturday, April 27, 8:30-11 a.m., Fishback Park, Denver Register as a volunteer


Fly Solo

All you need is a smartphone and the iNaturalist app. Any observations you take between Friday, April 26 and Monday, April 29 will count towards the project. You have up until Sunday, May 5 to identify as many observations as you can.


Próximamente preguntas frecuentes sobre City Nature Challenge.

Denver Audubon logo
Denver Parks and Recreation logo
High Line Canal Conservancy logo
City Nature Challenge organized by logo
2022 The Nature Conservancy logo

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