• Crabeater seal relaxing on a beach in Argentina
    This lounging crabeater seal from Argentina was one of over 1,250,000 observations made during the City Nature Challenge. (© María Regina Silva)
  • A long-nosed snake after a recent shedding
    A beautifully patterned long-nosed snake photographed in the Bay Area. (© Tony Iwane)
  • A hybrid species of lorikeet flaps its wings
    This lorikeet, observed just outside of Melbourne, is a hybrid of two or more species. (© jdagg)
  • A pair of endangered blue-sided tree frogs
    This duo of endangered blue-sided tree frogs was found in Costa Rica. (© Felipe Vega Con)
  • A critically endangered endemic flower from Orange County
    This flower photographed in Orange County, California is a critically endangered species found nowhere else on Earth. (© James Bailey)
  • A giant Australian cuttlefish cruises by
    A giant Australian cuttlefish cruises by a community scientist off the coast of Adelaide. (© David Muirhead)

SAN FRANCISCO, CA (May 10, 2021) — In its sixth year, the annual City Nature Challenge—one of the world’s largest community science events—has surpassed 1,000,000 wildlife observations for the first time! Over the four-day event held last weekend, more than 52,000 people across six continents participated however they could—from attending socially distant 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. Given the continued impact of COVID-19, this year’s Challenge forwent the competition component, focusing instead on providing a way for people to safely reconnect with nature and each other while contributing important biodiversity data from around the world.

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 400 cities across 44 countries. This year’s Challenge broke every previous record, tallying over 1,250,000 observations; engaging more than 52,000 observers; and recording nearly 45,000 species worldwide, including over 2,100 rare, endangered, or threatened species. This year’s Challenge was made possible thanks to the creativity and adaptability of hundreds of individuals and partner organizations, who found novel ways of empowering their respective communities to safely participate despite COVID-19.

“We are thrilled to surpass one million observations for the first time,” says Alison Young, co-director of Community Science at the Academy and co-founder of the Challenge. “Especially after such a challenging year, it is heartening to see so many people from around the world safely coming together to experience the restorative power of nature and reach such a momentous milestone.”

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

San Francisco Bay Area by the numbers

  • More than 2,200 observers
  • Over 32,100 observations submitted to iNaturalist
  • Contributors averaged 14 observations
  • More than 2,800 species documented
  • Most observed species: California poppy (Eschscholzia californica)

San Francisco Bay Area highlights

Highlights from around the Bay Area include a stunningly patterned long-nosed snake, a stern gaze from a great horned owl, the vulnerable and endemic Oakland mariposa lily, a prowling mountain lion caught on a camera trap, an otherworldly opalescent nudibranch, and a decaying endangered fin whale recently necropsied by the California Academy of Sciences and The Marine Mammal Center.

World by the numbers

  • More than 1,250,000 observations submitted to iNaturalist
  • Over 52,000 observers
  • Contributors averaged 24 observations
  • Over 45,000 species documented
  • Most observed species: Mallard (Anas platyrhynchos)

World highlights

Highlights from around the U.S. and the world include a hummingbird in Washington hunkered down in its nest, a threatened giant Australian cuttlefish scuttling by off the coast of Adelaide, a lounging crabeater seal in Argentina, a critically endangered endemic flower in Orange County, a jaguar prowling around northern Bolivia, a duo of endangered blue-sided tree frogs in Costa Rica, a rare multispecies hybrid lorikeet in Australia, Honduras’s first record of a species of hairstreak butterfly, and the expansion of the voracious invasive emerald ash borer beetle in Denton County, Texas.

“From common plants to endangered amphibians, every observation helps us reconnect with nature and contributes important biodiversity data that enables scientists and managers to better understand and protect our planet,” Young says. “To collectively produce over a million wildlife observations in a single long weekend is a truly remarkable feat—one we look forward to topping during next year’s Challenge!”

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.

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