Frequently Asked Questions

Hi Texas City Nature Challengers! We've pulled together this list of some of the most frequently asked questions we've heard over the past couple of City Nature Challenges. Hopefully this will help get everyone on the same page, but if your question isn't addressed here, feel free to ask us directly at or — Wendy and Craig, TPWD

The City Nature Challenge is a global, city-scale BioBlitz event that frames an urban biodiversity survey as a friendly competition between cities. It started in 2016 as a celebration of the first-ever Citizen Science Day with a friendly showdown between Los Angeles and San Francisco. In 2017, 16 cities across the US participated, and in 2018, the event went global, with 68 cities across the planet participating. In 2019, that number grew to over 150 cities worldwide.

Unlike many traditional biodiversity surveys, the City Nature Challenge is designed to assess biodiversity in the human-dominated landscapes in and around our major metropolitan areas. The data collected during this survey helps researchers and conservation agencies better understand how, when, and where plants and animals — from non-native invasives to native Species of Greatest Conservation Need — are distributed across urban landscapes.

Moreover, it presents a great opportunity to engage people in these urban areas with the nature around them. As we rebuild connections with the natural world, we create communities more invested in restoring and protecting it.

You can learn more on the City Nature Challenge website.

The observation part will state at 12:00 a.m. on Friday, April 26, 2024 and end at 11:59 p.m. on Monday, April 29, 2024.

The Identification period will continue from Tuesday, April 30, 2024 until 11:59 p.m. on Sunday, May 5, 2024. Please note that identifications can be made at any time during the event, so even though we have six days to wrap up identifications, don't wait until the last minute to begin!

When we say "cities", in Texas we are referring to major metropolitan areas. Our boundaries in iNaturalist will generally follow county boundaries.

To see which metro areas in Texas are participating, see City Nature Challenge Participating Texas Metro Areas Table for counties and websites.

Just as not all metro areas are the same size, not all participating areas in the City Nature Challenge are the same size — and that's great because it gives us information about biodiversity across a spectrum of developed areas. With respect to the metrics we'll be tracking globally, the organizers will be taking into account population and area in km2 for each participating city/metro.

The City Nature Challenge will use the iNaturalist platform to collect participant observations. To participate, you will need to sign up for a free iNaturalist account; all you need is a valid e-mail address and a username you create. You can enter your observations via the iNaturalist website or via the free phone apps (available for both Apple and Android phones).

iNaturalist is a free platform for collecting biodiversity data across the globe. Users upload their observations of organisms to the platform, and the community of users works together to identify and verify identifications of those organisms. Ideally, iNaturalist users not only upload observations, but also help make identifications for others' observations, too. Beyond being a simple database of observations, iNaturalist is a place to learn more about the nature around you, both from the taxa guide and from the other naturalists using the site. There is a place for everyone, from novices just learning about nature to professionals/experts.

You can learn more on the iNaturalist Frequently Asked Questions webpage.

There are several ways to participate! You can either find a local event hosted by a community partner or you can collection observations on your own or with your own group. As long as your observations are made during the data collection period (April 26 - 29) in your city's project place (the cluster of counties above) and uploaded to iNaturalist by May 6, 2021, they will count.

Thank you for hosting an event in support of the City Nature Challenge — it's partners like you that really make this event take off. Let us know you're interested in being a local partner with your event — e-mail either or so that we can you to the City Nature Challenge organizations for your city.

Typically, events fall into the following categories:

  • iNaturalist Training Events
    Can be scheduled any time leading up to the City Nature Challenge. These events train potential participants on the use of iNaturalist for data collection.

  • BioBlitz Events
    Should be scheduled Friday, April 26 through Monday, April 29, 2024. These are active data collection with participants making iNaturalist observations.

  • Identification Party Events
    Can be scheduled Tuesday, April 30 through Sunday, May 5, 2024. During ID parties, a group gathers with computers/tablets/phones to make identifications on iNaturalist observations for their area. A good WiFi connection is recommended.

With the new collection project format in iNaturalist, you no longer have to actively join the project or remember to add all of your observations to the project; iNaturalist will automatically find them if they are made in the right place and time for the project.

Note that this only applies to observations where the Geoprivacy is set to Open. Private observations won't be captured at all, as this setting means iNaturalist keeps your location information hidden from all other users. Observations set to Obscured may be captured in the project if they are well within the boundaries of the project area (Obscured will create up to a 10km area of uncertainty, so if you are close to a county boundary for your metro's place, it could end up not being counted if the system places it outside).

Making observations is only one part of the equation — we really need as much help as possible with adding identifications to all those iNaturalist observations! If for whatever reason you can't make observations during the City Nature Challenge, there is a critical role for you as an identifier. You don't need to be an expert in everything, or anything. If you can tell a plant from an animal, then you can be an identifier on iNaturalist. Often, observations come in that have no category at all ("Life" or "Unknown"), and simply placing these into a kingdom-level category is helpful, as it starts the process of narrowing the ID down. The more specific you can be, the better, but every increase in specificity helps.

You can make identifications from anywhere in the world as long as you're logged into iNaturalist as a user. So get comfy, grab a bowl of your favorite snack food, your field guides of choice, and let the IDs roll!

The sooner you can start uploading your observations the better, as this will mean they get identified sooner, but technically you can keep uploading observations made during the Observation period until the end of the Identification period (if you made the observation during the Identification period, sorry — it doesn't count).

We encourage you to start making Identifications for your area as soon as the first observations get uploaded to iNaturalist. The sooner you get observations uploaded and the identification process started, the more species your city gets to count.

Can you tell a plant from an animal? Then you can be an identifier on iNaturalist. Often, observations come in that have no category at all ("Life" or "Unknown"), and simply placing these into a kingdom-level category is helpful, as it starts the process of narrowing the ID down. The more specific you can be, the better, but every increase in specificity helps. The best rule of thumb is to identify things down to the level of specificity you feel comfortable with; if you feel confident with the genus, for example, stop there and don't make a wild guess on the species.

Identifiers can be from anywhere on the planet; if someone can help get the identifications closer to species level, it doesn't matter where they are.

Technically yes, but this is really against the spirit of the City Nature Challenge (perhaps not iNaturalist, though, if you're interested in tracking the progress of an organism — like a plant growing or caterpillar maturing — over time).

Sometimes a group finds a really exciting organism and everyone wants to observe it. That's technically ok, too, but really is double-counting, and it's one reason the City Nature Challenge tracks multiple metrics for the leaderboard. (Yes, leaderboard. Competitive types, I see you).

Technically, City Nature Challenge projects are not limited to only wild organisms, so observations on things like garden plants will not be eliminated, but we strongly encourage participants to focus on wild organisms. Note that captive/cultivated observations will not achieve Research Grade status and will not help your city compete with regards to that metric. How does iNaturalist define captive/cultivated? See more on the iNaturalist Help webpage "What does captive / cultivated mean?" section.

You can record both non-native/invasive AND native species for the City Nature Challenge. In addition to knowing more about native species in our urban areas, these data can give us insights into the types and extent of non-native species presence in cities and suburbs.

Yes, dead stuff counts! For some organisms, the unfortunate reality is that we most often encounter them as roadkill — and in iNaturalist and the City Nature Challenge, those are valuable data. Also, you can provide strongly diagnostic evidence of an organism without actually recording the organism itself (i.e. a tell-tale beaver chew pattern on a tree, a Barn Swallow nest, the "handprint" of a raccoon left in mud). Just remember that this type of evidence needs to be recorded and geotagged out in nature; please do not add preserved specimens from a collection or in a museum to iNaturalist.

While the City Nature Challenge iNaturalist projects aren't the place for your cute bumble-beagle, we'd love for you to share your adventures collecting iNaturalist observations together around town on our Texas Nature Trackers Facebook page and using the tag #CityNatureChallenge and #texasnaturetrackers on social media.

Getting the word out about our experiences with City Nature Challenge via social media is an important part of raising awareness of the biodiversity within our communities — so whether you're out with your bumble-beagle, family, class, friends, or just enjoying the experience alone, share your story and inspire others to get involved!

Hey there, you're really into this! The City Nature Challenge organizers have set up an umbrella project to summarize the results for all cities competing this year, see the iNaturalist City Nature Challenge 2024 Leaderboard webpage.

You can see the leaderboard (for Number of Observers, Species Count, and Observations), which contains links to each city's individual City Nature Challenge project page. On the individual city project pages, you can see which observers are at the top of the local leaderboard, too.


City Nature Challenge 2024 Participating Texas Metro Areas

Metro Area Counties iNaturalist Project Webpage
Abilene/Texas Big Country Callahan, Jones, Nolan, Shackelford,
Taylor, Tom Green
City Nature Challenge Texas Big Country
Amarillo Armstrong, Potter, Carson
Randall, Hutchinson
City Nature Challenge Amarillo
Austin Bastrop, Blanco, Travis, Burnet,
Williamson, Caldwell, Hays
City Nature Challenge Austin
Brazos Valley Brazos, Burleson, Grimes, Leon,
Madison, Robertson
City Nature Challenge Brazos Valley
Dallas-Fort Worth Collin, Kaufman, Dallas, Parker,
Denton, Rockwall, Ellis,
Tarrant, Johnson, Wise
City Nature Challenge Dallas-Fort Worth
El Paso El Paso City Nature Challenge El Paso
Houston-Galveston Austin, Harris, Brazoria, Liberty,
Chambers, Montgomery, Fort Bend,
Waller, Galveston
City Nature Challenge Houston-Galveston
Lower Rio Grande Valley Cameron, Starr, Hidalgo, Willacy City Nature Challenge Lower Rio Grande Valley
Lubbock Bailey, Cochran, Crosby, Dickens,
Floyd, Garza, Hale, Hockley,
King, Lamb, Lubbock, Lynn,
Motley, Terry, Yoakum
City Nature Challenge Lubbock
Port Aransas/Mustang Island Mustang Island, Port Aransas City Nature Challenge Mustang Island Texas
San Antonio Atascosa, Bandera, Bexar,
Gillespie, Goliad, Guadalupe,
Kendall, Kerr, Karnes,
Medina, Comal, Wilson
City Nature Challenge San Antonio
Tyler / East Texas Anderson, Cherokee, Gregg,
Henderson, Rusk, Smith,
Rains, Van Zandt, Wood
City Nature Challenge Tyler East Texas
Waco Bell, Bosque, Coryell, Falls,
Hamilton, Hill, McLennan,
Milam, Somervell
Heart of Texas City Nature Challenge
Walker & Trinity County Walker, Trinity City Nature Challenge Walker & Trinity County
Wichita Falls Archer, Baylor, Clay, Foard,
Hardeman, Jack, Montague,
Wichita, Wilbarger, Young
Wichita Falls City Nature Challenge


The City Nature Challenge is organized by the California Academy of Sciences and the Natural History Museum of Los Angeles County.

California Academy of Sciences Natural History Museum of Los Angeles County