2025 City Nature Challenge

BE ADVISED: On Saturday, April 26 and Sunday, April 27, nearby events at Exposition Park and the University of Southern California will impact traffic, parking, and wayfinding in the area. Please consider riding the Metro E (Expo) Line and exiting at USC/Expo station.

Side view of a child looking at leaf through a magnifying glass, against a blurry leafy green background

Global Event

2025 City Nature Challenge

Join an international effort to document nature in cities, taking place from April 25 to 28.

The City Nature Challenge is an international effort to document nature in cities, taking place from April 25 to April 28, 2025. The global event calls on current and aspiring community scientists, nature and science fans, and people of all ages and backgrounds to get outside and observe and submit pictures of wild plants, animals, and fungi during the Challenge dates in order to help scientists track real-time changes in our planet’s biodiversity and better understand wildlife conservation.

Take Part!

City Nature Challenge is about documenting nature where people live, especially in urban areas. Here’s how to participate in or near your home:

Explore your home or yard

What can you find in your house?
What can you see through your windows?
What are the wild plants growing in your backyard? (weeds count!)
What insects or other creatures are using the cultivated plants in your backyard as a habitat or a food source?
What observations can you make along the sidewalk in front of your house or apartment complex? (Always be mindful of traffic and safety.)
Check out more ideas for exploring nature in and around your home.

Explore your neighborhood

Take a walk and see what kinds of wildlife share your neighborhood.
Look up to spot birds sitting in trees or on powerlines and telephone poles.
Look down to find insects crawling on the pavement or underneath leaves.
What else might you find?
Visit your local park. Look in the grass, on plants, under benches and tables, and up in the trees. How many different species will you find?

How to Participate

Download the iNaturalist app from the App Store or Google Play.

Step 1: Find wildlife anywhere in L.A. County (or your local area).

Step 2: Take photos of WILD** plants & animals.

Step 3: Share Your observations in the iNaturalist app. If it's planted or taken care of by people it is not WILD. Mark it captive/cultivated!

Step 4: Learn more as your finds get identified.

**Wild means not captive or cultivated. Try not to take pictures of captive animals in zoos or aquaria and cultivated plants in your garden or at a nursery.

Events

Join us to meet your human and wildlife neighbors in L.A.!

Elephant Hill Habitat Survey
Saturday, April 26, 9am–12:30pm
Hosted by the Natural History Museum of Los Angeles County

In partnership with Save Elephant Hill and Coyotl + Macehualli, join hundreds of cities worldwide for community-led conservation in Los Angeles for the 10th annual City Nature Challenge at Elephant Hill! The City Nature Challenge is an annual 4-day urban habitat survey where people just like you in cities all over the world contribute photos of nature in their neighborhoods. These photos build a global urban biodiversity database for conservation, restoration, land management and research.

Take part at Elephant Hill by documenting wildlife with scientists from the Natural History Museum using your phone camera.

Your photos become data in a global effort to help understand and protect urban biodiversity, including nature at Elephant Hill!

Meet people protecting and restoring Elephant Hill from threats like offroading.

Partner Events Happening Throughout Los Angeles County

Thursday, April 17

Peninsula BioBlitz 2025 Training
Thursday, April 17, 6–7pm
Hosted by Palos Verdes Peninsula Land Conservancy

Join this virtual presentation to learn how you can help us collect information about biodiversity in the Nature Preserves using iNaturalist along our trails during the City Nature Challenge April 25-April 28.

Friday, April 25

City Nature Challenge at Descanso Gardens
Friday, April 25, 9am–7pm
Hosted by Descanso Gardens
(Requires admission or garden membership)

Descanso Gardens is joining the 2025 City Nature Challenge. Come explore and study Descanso Gardens’ unique botanical habitat.

Need help learning how to use iNaturalist? Check out our Community Science table during Cultivate on April 25 or sign up here and have instructions sent to your inbox.

City Nature Challenge at Rancho Los Cerritos
Friday, April 25, 10am–5pm
Hosted by Rancho Los Cerritos Foundation

Community science opportunity for groups or individulas documenting the biodiversity of the Rancho grounds. No cost but must register on our website to help us plan out guides schedules.

Santa Ana Zoo Mini-Bioblitz
Friday, April 25, 1–3pm
Hosted by the Santa Ana Zoo (an Orange County partner)

Help us document the biodiversity of Orange County! Meet us at the park in front of the Santa Ana Zoo to discover urban wildlife and practice your iNaturalist skills. Program is free to the public and does not require purchase of Zoo admission. You will need to purchase a ticket if you wish to enter the Zoo.

City Nature Challenge: Sunset Guided Nature Hike at Rocky Oaks
Friday, April 25, 6–8pm
Hosted by the Santa Monica Mountains Fund and Santa Monica Mountains National Recreation Area (National Park Service)

Join us on a guided hike at Rocky Oaks on Friday, April 25 from 6–8pm as we make observations and contribute to the 2025 City Nature Challenge. Expect an easy hike on uneven terrain and light elevation gain as we stop frequently to identify wildlife and take photos of organisms to upload on iNaturalist.

Plan ahead! Make sure you create an account with iNaturalist and have iNaturalist/Seek downloaded on your smart device prior to the event: https://www.inaturalist.org/

This is a free event with complimentary parking, no experience or expertise is required. Meet at the dirt parking lot of Rocky Oaks Park. Bring sun-protective layers, closed-toed shoes, water, a flashlight, and a device to take photos.

Black Light Event at Rancho Los Cerritos (ages 8 and up)
Friday, April 25, 7–9pm
Hosted by Rancho Los Cerritos Foundation
Space is limited, RSVP required

What flies around the Rancho at night? Visit the black light to see moths and other night-flying insects.

Saturday, April 26

2025 City Nature Challenge: LAX Dunes (CDIP)
Saturday, April 26, 8am–10am
Hosted by Los Angeles World Airports, Natural Resources Management

Please join us for some exploratory fun in the LAX Dunes! LAWA will host a bioblitz event in the northern LAX Dunes. Use your phones to take pictures of native plants and animals and submit your observations to iNaturalist!

City Nature Challenge 2025 at Willow Springs Park
Saturday, April 26, 9am–12pm
Hosted by the City of Long Beach Office of Climate Action and Sustainability

Exercise your community scientist skills and use the iNaturalist app to document local flora and fauna. Gain knowledge about some of Long Beach's biological richness and participate in a global event to contribute to community building. You'll get to use iNaturalist to contribute to the documentation of the biodiversity of Willow Springs Park. Through this, you will be able to explore the park as well as take a guided walk and participate in a scavenger hunt.

Cleaner Greener Whittier at Parnell Park
Saturday, April 26, 10am–12pm
Hosted by Cleaner Greener Whittier

Help us track and document the wildlife that call this park and its array of trees home, supporting efforts and conversation around the recent decision to remove these well established and well loved trees.

Santa Ana Zoo Mini-Bioblitz
Saturday, April 26, 10am–12pm or 1–3pm
Hosted by the Santa Ana Zoo (an Orange County partner)

iNaturalist Training at UCLA Mathias Botanical Garden
Saturday, April 26, 10am–3pm
Hosted by the UCLA Mathias Botanical Garden

The City Nature Challenge 10th Anniversary is here, and the UCLA Mathias Botanical Garden is excited to join! Our goal is to gather as many observations within the garden as we can. Our collection of plant life is host to plenty of both native and nonnative birds, insects, reptiles, mammals, and more! Join us as we host two hands-on iNaturalist training sessions and upload observations to better understand the biodiversity within our living museum.

City Nature Challenge at Rancho Los Cerritos
Saturday, April 26, 10am–5pm
Hosted by Rancho Los Cerritos Foundation

Youth groups or individuals for guided tour.

Nature Festival at Madrona Marsh
Saturday, April 26, 12-1pm
Hosted by Madrona Marsh Preserve and Nature Center
Call 310.972.7725 to reserve a spot on the Guided BioBlitz Tour

As part of the Marsh's annual Nature Festival, we will be hosting a guided bioblitz in the Preserve. Meet inside the Nature Center at 12pm and bring your binoculars, cameras, and phones out to the Preserve to record your observations of wildlife!

City Nature Challenge: Sunset Guided Nature Hike at Paramount Ranch
Saturday, April 26, 6–8pm
Hosted by the Santa Monica Mountains Fund and Santa Monica Mountains National Recreation Area (National Park Service)

Join us on a guided sunset hike at Paramount Ranch on Saturday, April 26 from 6PM to 8PM as we make observations and contribute to the 2025 City Nature Challenge. Expect an easy, short hike on uneven terrain as we stop frequently to identify wildlife and take photos of organisms to upload on iNaturalist.

Plan ahead! Make sure you create an account with iNaturalist and have iNaturalist/Seek downloaded on your smart device prior to the event: https://www.inaturalist.org/

This is a free event with complimentary parking, no experience or expertise is required. Meet us at the bridge on the dirt parking lot where we'll head together to the trailhead (across from the restrooms). Bring sun-protective layers, closed-toed shoes, water, a flashlight, and a device to take photos.

Sunday, April 27

City Nature Challenge: Guided Nature Hike at Rancho Sierra Vista
Sunday, April 27, 9–11am
Hosted by the Santa Monica Mountains Fund and Santa Monica Mountains National Recreation Area (National Park Service)

Plan ahead! Make sure you create an account with iNaturalist and have iNaturalist/Seek downloaded on your smart device prior to the event: https://www.inaturalist.org/

2025 LA City Nature Challenge Bioblitz - South Santa Monica Bay
Sunday, April 27, 10am–12pm
Hosted by Heal the Bay

To celebrate Earth Month, Heal the Bay's Safe Clean Water Program team invites you to join our 2025 LA City Nature Challenge BioBlitz—an event that began as a competition between Los Angeles and San Francisco and has now spread into a world-wide phenomenon!

2025 LA City Nature Challenge Bioblitz - Central Santa Monica Bay
Sunday, April 27, 10am–12pm
Hosted by Heal the Bay

City Nature Challenge at Rancho Los Cerritos
Sunday, April 27, 10am–5pm
Hosted by Rancho Los Cerritos Foundation

Youth groups or individuals for guided tour.

Santiago Creek ECO Center Mini-Bioblitz
Sunday, April 27, 10:30am–1:30pm
Hosted by the Santiago Creek ECO Center (an Orange County partner)

City Nature Challenge Bioblitz at Rancho Los Alamitos
Sunday, April 27, 1-4:30pm
Hosted by Rancho Los Alamitos

This year, Rancho Los Alamitos is participating in the City Nature Challenge (CNC) and we want you to join us! Observations are counted through the iNaturalist app. Learn from staff and volunteers on how to upload your wildlife observations. Tour our gardens while looking for wildlife. Join us for self-guided scavenger hunts with small, free giveaways. RSVPs encouraged; free for all.