San Francisco helped lead the biggest nature census on the planet this year. The 11th annual City Nature Challenge, held April 24–27, wrapped up with more than 3 million wildlife observations made by over 106,000 community scientists around the world — a brand-new record.
What began in 2016 as a friendly competition between the California Academy of Sciences in San Francisco and the Natural History Museum of Los Angeles County has blossomed into a global movement. This year, 754 cities across six continents joined in, documenting more than 76,000 species in just four days.
From a long-tailed weasel spotted in the Bay Area to a pink glowworm photographed across the Pacific, every snapshot became part of real science. The Academy’s Director of Community Science, Rebecca Johnson, reflected on the magic of the moment: while she photographs a flower in San Francisco, more than 100,000 people are doing the same in the places they call home.
San Francisco can be proud — the city that started it all continues to inspire a worldwide love of nature, one photo at a time.
Photo: California Academy of Sciences


