In its seventh year, the annual City Nature Challenge—one of the world’s largest community science events—has surpassed 1,690,000 wildlife observations for another record-breaking year! Over the four-day event held last weekend, more than 67,000 people across six continents participated however they could—from attending local wildlife surveys to finding the species in their own homes—to document the wondrous diversity of wild plants, animals, and fungi that share our planet using the free mobile app iNaturalist. From observations of critically endangered and elusive species to sightings of species outside of their known ranges, the City Nature Challenge underscores the power of community science in tracking real-time changes in our planet’s biodiversity—especially in urban areas. 

Started in 2016 by the California Academy of Sciences and the Natural History Museum of Los Angeles County as a friendly competition between San Francisco and Los Angeles metro areas, the Challenge has expanded to over 445 cities across 47 countries. This year’s Challenge broke every previous record, tallying over 1,690,000 observations; engaging more than 67,000 observers; and recording over 50,000 species worldwide, including over 2,200 rare, endangered, or threatened species. The highest number of observations were tallied in La Paz, Bolivia, where over 4,000 participants made more than 130,000 observations during the Challenge weekend! This year’s Challenge was made possible by the hundreds of individuals and partner organizations around the globe who empowered their respective communities to safely explore nature in their neighborhoods. 

“Biodiversity research tends to focus on untouched places, so cities are often overlooked scientifically,” says Alison Young, co-director of Community Science at the Academy and co-founder of the Challenge. “Observations made during the Challenge provide critical insights into the biodiversity of urban environments, allowing us to make more informed conservation and land management decisions.” 

See below for highlights for this year’s City Nature Challenge.

San Francisco Bay Area by the numbers

  • Over 31,200 observations submitted to iNaturalist
  • More than 2,000 observers
  • Contributors averaged 15 observations
  • More than 3,000 species documented
  • Most observed species: Ithuriel’s spear (Triteleia laxa)

San Francisco Bay Area highlights

Highlights from around the Bay Area include a glow-in-the-dark scorpion, a dancing trio of black-necked stilts, a vulnerable and endemic species of lichen, two urban coyotes—one with a set of ear tags—strolling through Golden Gate Park, an endangered foothill yellow-legged frog, and the remarkably well-camouflaged Blainville’s horned lizard. 

World by the numbers

  • More than 1,690,000 observations submitted to iNaturalist
  • Over 67,000 observers
  • Contributors averaged 25 observations
  • Over 50,000 species documented
  • Most observed species: Common dandelion (Taraxacum officinale)

World highlights

Highlights from around the U.S. and the world include a patriotic pair of scissor-tailed flycatchers in Texas, a whiskered tern diving for a snack in Hong Kong, a male moor frog sporting its breeding hues in Russia, a bloom of blue blubber jellyfish off the coast of Sydney, a giant squid stranded on South Africa’s Western Cape, New Zealand’s largest endemic sea slug, a brilliant blue pixie’s parasol mushroom in Australia, a red squirrel hard at work in Canada, a carnivorous and critically endangered round-leaved sundew in Tennessee, a plump and proud cape fur seal in Cape Town, and a robber fly making a meal out of an unlucky wasp in Brazil. 

“Strengthening our connection to nature and each other is at the heart of the City Nature Challenge, and we’re thrilled to see just how many people share the same excitement and curiosity for their local wildlife,” Young says. “We often think we have to go far to see nature, but all we really need to do is step outside.” 

About the California Academy of Sciences
The California Academy of Sciences is a renowned scientific and educational institution with a mission to regenerate the natural world through science, learning, and collaboration. Based in San Francisco’s Golden Gate Park, it is home to a world-class aquarium, planetarium, and natural history museum, as well as innovative programs in scientific research and environmental education—all under one living roof. Museum hours are 9:30 am – 5:00 pm Monday – Saturday, and 11:00 am – 5:00 pm on Sunday. Admission includes all exhibits, programs, and shows. For daily ticket prices, please visit www.calacademy.org or call (415) 379-8000 for more information.  

About the Natural History Museums of Los Angeles County
The Natural History Museums of Los Angeles County (NHMLAC) include the Natural History Museum in Exposition Park, La Brea Tar Pits in Hancock Park, and the William S. Hart Museum in Newhall. They operate under the collective vision to inspire wonder, discovery, and responsibility for our natural and cultural worlds. The museums hold one of the world’s most extensive and valuable collections of natural and cultural history—more than 35 million objects. Using these collections for groundbreaking scientific and historical research, the museums also incorporate them into on- and offsite nature and culture exploration in L.A. neighborhoods, and a slate of community science programs—creating indoor-outdoor visitor experiences that explore the past, present, and future. Visit NHMLAC.ORG for adventure, education, and entertainment opportunities.