City Nature Challenge tallies over 1.27 Million Wildlife Observations

Over 52,000 community scientists from 419 cities around the world document more than 2,100 rare, endangered, or threatened species in four-day community science effort

Species observed include Almirante Blanca butterfly, the first documented sighting of this species in Argentina and the southernmost record in all of South America, and critically imperiled Simpson’s grasspink flower in Florida

Left: Almirante Blanca butterfly  © matiascabezas; Right: Simpson's Grasspink flower © joemdo

Los Angeles, CA (May 10, 2021) — The City Nature Challenge (CNC) results are in! More than 52,000 people across six continents documented over 1.27 million wildlife observations for the 6th annual community science initiative. From a sighting of a critically imperiled flower from the U.S., to documenting an uptick in urban wildlife activity due to shelter-in-place orders, the observations gathered help scientists create a valuable snapshot in time of urban biodiversity.

The global event called on current and aspiring community scientists, nature and science fans, and people of all ages and backgrounds to observe and submit pictures of wild plants, animals, and fungi from April 30 to May 3. In light of COVID-19, this year’s Challenge was not a competition. Instead, participants were encouraged to embrace the collaborative aspect of sharing observations online with a digital community and celebrate the healing power of nature safely from home.

People of all ages and science backgrounds submitted pictures of wild plants and animals using the free mobile app iNaturalist. From sightings of critically endangered species to documenting urban wildlife, the competition underscored the power of community science to track real-time changes in our planet’s biodiversity.

After co-founding and organizing the first-ever City Nature Challenge in 2016 as a competition between the Los Angeles and San Francisco metro areas, the Natural History Museum of Los Angeles County (NHM) and the California Academy of Sciences expanded the initiative to 419 cities across 44 countries. This year’s Challenge tallied over 1.27 million observations, including over 2,100 rare, endangered, or threatened species; engaged more than 52,000 observers (more than ever before); and recorded over 45,000 species worldwide. 

“It has been amazing to see so many new cities and communities of  people from around the globe come together to celebrate nature during this year’s event, especially in light of the continued pandemic,” says Lila Higgins, co-founder of the City Nature Challenge and Natural History Museums of Los Angeles County (NHMLAC) Senior Community Science Manager. “I’m still in a state of awe that over 52,000 people were compelled to connect with nature in this way, and even though so many of us still have to be apart, people came together virtually to make over 1.27 million records of living beings on our planet!”

The Challenge would not be possible without the hundreds of partner organizations around the world which empowered their respective communities to document local biodiversity. “Organizing the City Nature Challenge in Los Angeles is a team effort,” says Amy Jaecker-Jones, NHMLAC Community Science Coordinator. “We work with an amazing group of non-profit organizations and governmental offices. While the COVID-19 pandemic once again restricted our ability to hold big, in-person bioblitz events, organizers rallied to hold a series of virtual events leading up to the City Nature Challenge and some sites were able to station interpretive staff at various locations to engage visitors in making observations. It really is the collaborative work of all of our partners and their connections within different communities that make the City Nature Challenge a success.”

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

Los Angeles County by the numbers

  • 1,507 observers 
  • 2,639 species documented 
  • 22,045 observations submitted to iNaturalist 
  • Most observed species: western fence lizard (Sceloporus occidentalis)

View all L.A County iNaturalist results here.

Los Angeles County highlights

  • Gabb’s Checkerspot Butterfly. This vulnerable butterfly species was recorded twice this year and found in two different areas of eastern L.A. county. 
  • San Clemente Snail.  Only one observation of this critically imperiled snail was made during the City Nature Challenge this year. It exists on San Clemente Island and nowhere else in the world.
  • Green Sea Turtle. Two sea turtles were observed near the mouth of the San Gabriel River. This threatened species has made a home near the warm water outflows of a local power plant, and represents the northern-most population of this sea turtle species. 
  • Gopher Snake. Although a well-known resident of the L.A. area, gopher snakes are rarely seen. Thanks to the thousands of community scientists taking part in L.A., together we clocked 16 observations. This individual was sunning themselves on a hilltop in Mount Washington, with an amazing view of the city below.

World by the numbers

  • More than 52,000 observers
  • More than 1.27 million observations submitted to iNaturalist
  • Over 45,000 species documented, including over 2,100 rare, endangered, or threatened species
  • Most observed species: Mallard duck (Anas platyrhynchos)

View all global iNaturalist results here.

World highlights
Highlights from around the U.S. and the world include an Almirante Blanca butterfly, the first documented sighting of this rare butterfly species in Argentina and the southernmost record in all of South America; a critically imperiled Simpson’s grasspink flower in Florida; a first record of an introduced Turkish snail, found in the Czech Republic at a railway shipment yard; a rarely seen orchid bee in Columbia, the first time it has been recorded in the country on iNaturalist and also the first ever  record of it on the platform; and a near threatened witches’ cauldron fungus found in Russia. 

The current landscape of urban biodiversity is poorly understood. As global human populations grow increasingly concentrated in cities, documenting urban biodiversity—and our impact on it—is a crucial part of understanding our shared future. Large pools of data, including those built by iNaturalist and natural history museums, aid in scientific research and help land managers make informed conservation decisions for humans to sustainably coexist with regional plant and animal life.

In 2020, the Challenge tallied over 815,000 observations, including over 1,300 rare, endangered, or threatened species; engaged over 41,000 observers; and recorded over 45,300 species worldwide.

Urban nature initiatives at the Natural History Museum of Los Angeles County (NHM)
In the last several years, NHM has shifted its attention to include not just natural and cultural history, but living nature—and specifically, the nature of L.A. With the 2013 addition of the outdoor Nature Gardens and their companion indoor exhibit, the Nature Lab, the museum has onsite venues that engage Angelenos in an investigation of the nature around them. Additionally, the museum’s Urban Nature Research Center (UNRC) and Community Science Program help spotlight ways to boost and sustain Los Angeles’ biodiversity. UNRC and Community Science Program initiatives include the City Nature Challenge, co-founded with the California Academy of Science; SuperProject, the world's largest urban biodiversity survey; RASCals (Reptiles and Amphibians of Southern California); SLIME (Snails and Slugs Livings in Metropolitan Environments); BioSCAN (Biodiversity Science: City and Nature); Southern California Squirrel Survey; L.A. Spider Survey; and more. Visit NHMLAC.ORG/nature for more information.

About the Natural History Museums of Los Angeles County (NHMLAC)
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.

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Sally Márquez
(213) 373-3217