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City Nature Challenge

Cities around the world collaborate to share observations of nature in the 2025 City Nature Challenge.

Started in 2016 as a competition between Los Angeles and San Francisco, the City Nature Challenge (CNC) has grown into an international event, motivating people around the world to find and document wildlife in their own cities. Run by the Community Science teams at the California Academy of Sciences and the Natural History Museum of Los Angeles County (NHM), 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 what can be accomplished when we all work toward a common goal.
2 parts
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The 2025 CNC takes place in
1
April 25 – April 28, 2025
Taking pictures of wild plants and animals.
2
April 29 – May 4, 2025
Identifying what was found.
Results will be announced on Monday May 5, 2025.

Taking part is easy

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Find Wildlife
It can be any plant, animal, or any evidence of life found in your city.
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Take picture
Take a picture of what you find. Be sure to note the location of the critter or plant.
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Share!
Share your observations through iNaturalist or your city's chosen platform.

2024 Totals

2,436,844
Observations
65,682+
Species
83,528
Participants