City Nature Challenge: Explore, Document, and Protect Urban Biodiversity

The City Nature Challenge is a global community science event where participants use the iNaturalist app to document urban biodiversity, contributing valuable data to support conservation and scientific research.

1 minute read

March 10, 2025, 6:00 AM PDT

By Clement Lau


Yellow bird with black head sitting on power line.

SLIZARZA / Adobe Stock

The City Nature Challenge is a global community science event that encourages people to observe and document biodiversity in their cities. Participants use the iNaturalist app to take photos of plants, animals, and fungi, contributing valuable data to help scientists better understand urban ecosystems. The event fosters a deeper connection with nature while promoting conservation efforts.

Held annually over four days, the challenge brings together cities worldwide in a friendly competition to record the most observations, identify species, and engage the most participants. It begins with an observation period, followed by time for identifying species and compiling results. The event is open to everyone, from seasoned naturalists to casual nature lovers.

Started in 2016 by the California Academy of Sciences and Natural History Museum of Los Angeles County, the City Nature Challenge has grown into an international effort spanning hundreds of cities. It highlights the importance of urban biodiversity, encourages environmental stewardship, and inspires communities to explore and appreciate the nature around them.

Saturday, March 1, 2025 in City Nature Challenge

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City Nature Challenge: Explore, Document, and Protect Urban Biodiversity

The City Nature Challenge is a global community science event where participants use the iNaturalist app to document urban biodiversity, contributing valuable data to support conservation and scientific research.

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