Connecting with Nature Through Your Phone

During this year’s international City Nature Challenge, tens of thousands of people across the world went outside to take photos, document, and identify animal and plant species in their communities.

1 minute read

June 27, 2023, 5:00 AM PDT

By Clement Lau


Close-up of hands holding mobile phone up to a plant to take a photo

K.Decha / Adobe Stock

The City Nature Challenge is an international effort for people to find and document plants and wildlife in cities across the globe. It is a bioblitz-style competition where cities are in a friendly contest with 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 first City Nature Challenge in 2016 was an eight-day competition between Los Angeles and San Francisco, engaging residents and visitors in documenting nature to better understand urban biodiversity. 

As reported by Bella Isaacs-Thomas, over 66,000 participants worldwide contributed to a total of almost two million observations of plants, animals, fungi and any other living things between April 28 and May 1, 2023. Observers documented more than 57,000 species, including over 2,570 species that are rare, threatened, or endangered. 

During the four-day challenge, many participants snapped photos on their smartphones and uploaded them to iNaturalist, an app designed to document and identify wildlife. The city of La Paz in Bolivia took the gold for most participants this year. Those observers also made both the highest number of observations and spotted the most species. Over 3,000 people in that city spotted 5,344 species and made more than 126,000 observations collectively.

Wednesday, May 10, 2023 in PBS News Hour

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