
The City Nature Challenge is an international effort for people to find and document plants and wildlife in cities across the globe. It’s a bioblitz-style competition rooted in community science where cities are in a contest against each other to see who can make the most observations of nature, who can find the most species, and who can engage the most people. CNCSoFlo encompasses Monroe, Miami-Dade, Broward, and Palm Beach Counties. South Florida has an array of unique environments, both terrestrial and marine, where diverse flora and fauna can be found just outside your door.
Help South Florida win the City Nature Challenge! The competition is conducted through an app called iNaturalist, which collects geotagged species data so that community scientists (like you!) can contribute to research in biodiversity science and natural resource management. Download iNaturalist for free, join our iNaturalist project, and start taking pictures of wildlife. Follow CNCSoFlo on Instagram for tips, resources, and event updates.
The City Nature Challenge takes place over two weekends:
The first weekend is all about wildlife observations! Any observations made within our SoFlo boundary during weekend one will contribute to our efforts in the City Nature Challenge! Participation occurs through an app called iNaturalist, where you can take and upload pictures of flora, fauna, and fungi. When you upload your photo, identify the species to the best of your ability. If in doubt, leave it unidentified.
The second weekend is all about identification! Connect in person or virtually with your South Florida peers to best identify species observed in your area. Are you familiar with South Florida species? Hop on iNaturalist and help identify local observations! Make sure to check back on your own observations, as your peers confirm your identifications and might suggest alternatives.
City Nature Challenge 2026
April 24-27, 2026
Take part in a global community science effort to enhance our understanding of the natural world!
City Nature Challenge Information
Important CNC Dates:
- Make and share observations: April 24 – 27.
- Get all your observations uploaded and work on identifying them: April 28 – May 3.
- Results announced: Monday, May 4.
What are the boundaries of CNCSoFlo?
The CNCSoFlo encompasses Monroe, Broward, Miami-Dade, Palm Beach, and Collier counties.
Do I need to be at an official event to participate?
No, all you need to do is upload observations to iNaturalist during the dates of the competition. Events are just a fun way to intentionally participate in the CNC and connect with other link-minded people.
What if I can’t get all of my photos uploaded before April 27?
Photos taken between April 24 – 27 can be uploaded until May 4 at 9 a.m. and will be added to your city’s CNC project.
What is a bioblitz?
A bioblitz is a short period of time where scientists, community members, students, and families come together to record as much wildlife as possible within a designated area. This helps us understand an area’s biodiversity over time. Events can take place at the park, on the playground, underwater, or even on your front porch. For example:
- Guided nature walk
- Kayak or paddle tour
- Snorkel or dive
- Parks in the Dark
- iNaturalist Training
What is iNaturalist?
iNaturalist is a free platform—both a website and app—to record observations of plants and animals in nature. You use photographs to share what you’ve found, which contributes to a global dataset of biodiversity information used for both science and conservation. Making observations is as simple as taking photos of organisms (or evidence of those organisms, like tracks, nests, shells, or skulls.) iNaturalist will suggest possible identifications, and then when you upload those observations, the iNaturalist community works together to refine and confirm the identifications. Learn more about iNaturalist here.
Can I get service hours?
We know many students are looking for volunteer opportunities for school and ways to give back to the environment. Here’s how to receive service hours for participating in CNC:
- Create a FREE account on iNaturalist
- Get outside and photograph wildlife, or evidence of wildlife
- Upload these photos either through the iNaturalist smartphone app or inaturalist.org
- Email muve@frostscience.org with your username so we can confirm you have uploaded observations. Please include your full name in the subject line
- For every 10 observations you will receive an hour of community service, maximum of 10 hours (100 observations.)
Have any more questions? Email conservation@frostscience.org.
South Florida 2025
2025 marked another record-breaking year for CNCSoFlo. Although our species and observation count decreased, we improved our total number of observations.
- 31,223 observations
- 744 observers
- 3,491 species
With 669 cities around the world participating this year, South Florida stood out once again, ranking in the top 5% across every category! We’re incredibly grateful to our dedicated community of observers, organizers, and identifiers who helped shine a spotlight on the incredible biodiversity that makes South Florida so special.
Photo by @tarruck (Chelonia mydas Green Sea Turtle)
Photo by @zlang8 (Ardea alba Great Egret)
South Florida 2024
2024 was another great year for the CNCSoFlo. We improved on our total observations and unique species observed.
- 28,910 observations
- 843 observers
- 3,499 species
This year, there were 690 cities competing, and we finished in the top 4% in every category! We are so proud of all of our South Florida citizen scientists, organizers, and identifiers. Thank you for helping us showcase South Florida’s beautiful and unique biodiversity.
Photo by @lt422 (Dingy Purplewing)
Photo by @er-birds (Black Mangrove)
South Florida 2023
In 2023, we added Palm Beach County to the CNCSoFlo boundary and it made a huge difference. All of our metrics increased for the third year in a row and we more than doubled our number of observations.
- 23,098 observations
- 1,107 observers
- 3,098 species
Huge thank you to everyone who hosted events, observed, identified, and spread the word about the 2023 CNC!
Photo by @monics (Danaus gilippus Queen Butterfly)
Photo by @coreytcallaghan (Clathrus crispus)
South Florida 2022
We improved on all of our metrics this year with more observations, species and participants than ever before.
- 11,349 observations
- 593 observers
- 2,116 species
Despite beating our own numbers, we dropped in ranking in all categories. There were more competing cities than ever before, and some seriously fierce challengers. However, as South Florida does, we worked hard and celebrated ever harder. Cheers, to our biodiversity!
Photo by @unlikelycharming (Amethyst Hairstreak)
Photo by @kuchipatchis (Pink Sundew)
South Florida 2021
City Nature Celebration Results:
- 10,327 observations
- 582 observers
- 1,978 species
Photo by @caporali (Felimare olgae nudibranch)
Photo by @eridanxharahi (Flat-collared Beewolf)
South Florida 2020
City Nature Celebration Results:
- 8,518 observations
- 472 observers
- 1,784 species
Photo by @juddpatterson (Big Cypress fox squirrel)
Miami & Upper Keys 2019
This year we expanded our boundary from Miami-Dade to include the Upper Keys. Quite the collaboration! Check out our results and favorite finds.
- 12,179 observations
- 556 observers
- 1,875 species