Community Scientists are Invited to Participate in the Global City Nature Challenge April 30 – May 3, 2021

Sixth annual challenge to document biodiversity grows to over 400 participating cities on six continents; results announced on May 10.

Left: Insect on a leaf, right: person taking photo of flower

Los Angeles, CA (April 1, 2021) – As community science initiatives—which provide a safe way to connect people with nature and each other during the pandemic—continue to grow in popularity, this year’s sixth annual City Nature Challenge is expanding to more than 400 cities across six continents. Beginning on Friday, April 30 at 12:01 am in each time zone, the Challenge runs through Monday, May 3, 11:59 pm. The global event, co-organized by the Natural History Museum of Los Angeles County (NHM) and San Francisco’s California Academy of Sciences, calls on current and aspiring community scientists, nature and science fans, and people of all ages and education backgrounds to observe and submit pictures of wild plants, animals, and fungi using the free mobile app iNaturalist. From Friday, April 30 to Monday, May 3, participants can upload their observations to the app, with identifications happening from Tuesday, May 4 to Sunday, May 9. Final results will be announced on Monday, May 10. 

“At its core, the City Nature Challenge celebrates science by encouraging community engagement with nature throughout the diverse neighborhoods comprising Los Angeles County,” said Dr. Lori Bettison-Varga, President and Director of the Natural History Museums of Los Angeles County. “Although many of us have spent the past year in isolation, the Challenge provides us with the opportunity to safely and remotely unite, connect with urban nature, and contribute to scientists’ collective global knowledge. I have seen the benefit of spending time outside observing and studying my natural surroundings, and I encourage all community members and participants around the world to safely search, discover, and enjoy the outdoors.”

After launching the first-ever City Nature Challenge in 2016, the Natural History Museum of Los Angeles County and California Academy of Sciences are hosting their sixth—and largest—effort. Nature is all around us; in our cities, neighborhoods, and even in our homes. One of the best ways to study nature and its biodiversity is by connecting scientists and local community members through community science. As global human populations become increasingly concentrated in cities, it’s more important than ever to document urban biodiversity and help ensure the future of plants and wildlife. Large pools of data built through iNaturalist, natural history museums, and science organizations help leaders make informed conservation decisions that allow both human and natural communities to thrive.

In response to the pandemic, this year’s Challenge will not be focused on competition, but rather global collaboration. "Last year we had over 41,000 people take part in the Challenge, more than in any of the previous years,” said Lila Higgens, NHMLAC’s Senior Manager of Community Science, and co-founder of the Challenge. “This year we anticipate 50,000 people taking part, even though we can't physically be together. It will be amazing to see what communities around the globe can accomplish in the name of urban biodiversity—I think we're going to see over a million observations in this year's City Nature Challenge." 

For both budding and veteran community scientists, joining in is easy: 

  1. Find wildlife in your home, neighborhood, backyard, or anywhere else! It can be any wild plant, animal, fungi, slime mold, or any other evidence of life, such as scat, fur, tracks, shells, or carcasses. Check out this guide for tips on finding the surprisingly abundant biodiversity in and around your own home!
  2. Take pictures of what you find using iNaturalist.
  3. Learn more as your observations are identified.

With travel restrictions due to the pandemic, scientists more than ever rely on observations from community scientists for important findings. During the 2020 City Nature Challenge, despite the challenges posed by the coronavirus pandemic, participants in Miami spotted an amethyst hairstreak butterfly, a species nearly extirpated from the United States. In Panama, community scientists documented a vibrant—and critically endangered—harlequin frog. And in Washington D.C., participants recorded Arlington County’s first observation of a white-spotted slimy salamander in over 40 years. Over 1,300 endangered, endemic, or data deficient species were recorded during the 2020 City Nature Challenge. This influx of information gives scientists, educators, urban planners, and policymakers insight into the biodiversity of locations throughout the world. 

Participants can also prepare to learn more about the nature surrounding neighborhoods from NHM’s book Wild L.A.: Explore the Amazing Nature In and Around Los Angeles, co-written by our very own Lila Higgins and Greg Pauly. It tells the stories of Los Angeles’ surprising nature, its plants and animals, and how humans interact with all of them. Learn more about this new kind of nature guide at NHM.ORG/wild-la.

Local support for the City Nature Challenge is generously sponsored by Boeing and the Los Angeles Department of Water and Power.

NHM City Nature Challenge Virtual Events

Get Ready for the City Nature Challenge this Earth Day!
April 22 at 6 pm

The City Nature Challenge is an annual competition between 100s of cities around the world that helps people better understand urban biodiversity by having them find and document nature in their community. In celebration of Earth Day and in preparation for the 2021 City Nature Challenge, we'll take a look at how community scientists are making a global impact by getting outdoors and looking closely at nature all around us. As a bonus, we’re offering an iNaturalist training so you’ll be ready to join the challenge! Visit NHM.ORG/events on April 15 for more information.

City Nature Challenge Virtual ID Party
Tuesday, May 4 at 7 pm

Join NHM staff & scientists in a virtual ID party where they will be identifying observations made during the City Nature Challenge to contribute to a global database of scientific research. No experience is necessary to participate. The event will include an introduction to iNaturalist's Identify Tool and tips for becoming a better identifier. 

More Information and Education Toolkit

Signing up is easy and free. Visit from your browser, or download iNaturalist from the Apple App Store or Google Play store. 

Social Media
Twitter handle: @citnatchallenge

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.

About the California Academy of Sciences
The California Academy of Sciences is a renowned scientific and educational institution dedicated to exploring, explaining, and sustaining life. 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 education—all under one living roof. When open, our 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 reopening information and daily ticket prices, please visit or call (415) 379-8000 for more information.

Image Credits
Left: City Nature Challenge participant pointing to an insect on a leaf.  Courtesy of the Natural History Museums of Los Angeles County (NHMLAC).

Right: City Nature Challenge participant taking photo of flower. Courtesy of the Natural History Museums of Los Angeles County (NHMLAC).

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Sally Márquez
(213) 373-3217