A young girl crouches down next to a tall leafy plant to take a photo with her cell phone.
Bioblitz A girl takes a photograph of a species of plant to upload to iNaturalist. © Devan King/TNC

Stories in Maryland/DC

City Nature Challenge

Discover and document the biodiversity of our urban spaces.

By Deborah Barber, Director of Land Management, Maryland/DC Chapter | May 10, 2019

| Last updated March 03, 2021

The City Nature Challenge (CNC) is an international citizen science effort to discover and document plants and wildlife in cities across the globe. The observation period of CNC 2021 will take place April 30 - May 3.

As with so many aspects of our lives, the City Nature Challenge has been impacted by COVID-19. To embrace the healing power of nature, and encourage the celebratory aspect of the CNC, participants are encouraged to safely document biodiversity in whatever ways they can, including from the safety of their own homes.

Explore our collection of recorded webinars for guidance and tips for recording observations in the iNaturalist app, engaging children with nature using the iNaturalist and Seek apps, tips and tricks to elevate your nature photography, and guidance on properly identifying CNC observations.

Maryland/DC Director of Land Management Deborah Barber is an avid member of the CNC community.  Here she shares her City Nature impressions and observations.

What kind of wild species can you spot at one-minute past midnight on a rainy spring night?

A close up macro view of a black fly sitting on a dried brown leaf.
Flesh Fly (Family Sarcophagidae) observed during the 2020 City Nature Challenge. © Deborah Barber

That’s the question DC-area citizen scientists ask themselve each year. There’s stiff competition to be the first person to post a photo of a wild organism to the iNaturalist app, and become the first observer in the Washington, DC, City Nature Challenge.

The City Nature Challenge is a fun, friendly competition that encourages people to discover and document the biodiversity of our urban spaces. Held each year among metropolitan areas worldwide, the aim is to find out which city can spot the greatest number of wild species, find the most diversity of species and engage the most observers. 

The event has grown by leaps and bounds since it began in 2016. Participants turned out in strength in 2020, despite the limits and precautions necessitated by the Covid-19 pandemic. 244 cities took part, reporting 815,258 observations and documenting more than 32,600 species.

One exciting find for the DC metro was a white-spotted slimy salamander (Plethodon cylindraceus) observed by a high school student in Arlington, VA. Endemic to the eastern US, this was the first sighting recorded in the county since 1977.

Zoom In, Zoom Out

iNaturalist, like The Nature Conservancy itself, is both deep and broad, highly local and powerfully global.  Zoom in, zoom out, you’ll see amazing things at every level.

Two beetles sit on a dark green leaf. The insects have a black body with a reddish cream marking on the back. Two black stripes on their backs resemble wings.
Asian Lady Beetle (Harmonia axyridis) pupae on plant in Lyon Park, Maryland native plant garden. © Deborah Barber / TNC

Zoom in: I posted a photo of a ladybeetle larva in my garden, then learned from other users that the Asian species has forked bristles; the natives’ bristles are single-tipped.  Now I know what to look for! Zoom out from any observation and you can see the global distribution of that species.

With a few more clicks, you can see how each organism fits into the entire taxonomical tree of life. Likewise, with TNC, I can spend a morning at work monitoring a plant found only in one small patch in Maryland, then in the afternoon share conservation strategies with TNC colleagues from Mongolia, China or Indonesia.

iNaturalist and TNC are both constantly learning and evolving.  iNaturalist’s computer vision, added in 2017, becomes smarter as users identify photos of organisms.

When I started working at the Maryland/DC Chapter, one of my first plant monitoring projects was documenting the steady decline of a rare wildflower, Canby's dropwort (Oxypolis canbyi). Now we have learned that it needs fire to thrive. We are burning its habitat and watching it multiply, and we are working with partner organizations to develop regional strategies to develop a more fire-friendly culture for natural area managers.

Friendly Competition

I’m not normally a competitive person, but when the City Nature Challenge begins, I will be out at midnight helping the DC area make the best possible showing. In 2020 the region ranked 3rd for both number of observers and number of research grade observations and 9th for number of species.

So, what observations have DC-area iNaturalists submitted in the moments past midnight?  Photos of a flashlight-illuminated ichneumonid wasp, a shield lichen, raccoon tracks on a trash can, a kitchen pantry moth and an audio file of a mockingbird singing its late-night song all have contributed to our picture of the diversity of life in Washington, DC.

City Nature Observations

Three children face a tall green bush examining the thick leaves. They are each holding long handled butterfly nets.
City Nature Challenge 2019 Young naturalists on the hunt for critters during the Maryland/DC chapter's "Moths in the Morning" guided hike. © Bridget Moynihan / TNC
Macro, upside-down view of a brown spider crawling on a ceiling.
Woodlouse Spider (Dysdera crocata), one of the first observations of the 2019 City Nature Challenge, spotted at 12:05 a.m. © Deborah Barber
A night photo with flash of a small rabbit sitting in a suburban front yard. The rabbit is sitting on a bare patch of dirt next to a wide concrete sidewalk.
Eastern Cottontail (Sylvilagus floridanus). On of the first observations of the 2018 City Nature Challenge, recorded at 12:10 am. © Deborah Barber / TNC
View looking up through a shallow plastic container of a four-legged winged insect. The insect has a thin body and nearly translucent wings.
Genus Aedes Observed during the 2019 City Nature Challenge. © Deborah Barber
Eight segments of fungus on the bark of a tree. The segments are shaped like fans with brown and white stripes.
False Turkey Tail (Stereum ostrea) observed during the 2020 City Nature Challenge. © Deborah Barber
Two women stand on opposite sides of a large tree trunk, smiling and posing while hugging the tree.
City Nature Challenge 2019 TNC's Bridget Moynihan and naturalist Melanie Choukas-Bradley show their love for nature during the Maryland/DC chapter's "Capitol Trees" guided hike. © TNC
Twelve people gather around a woman during a guided hike in the city. The woman is crouched down in front of a child describing the leaf she is holding.
Capitol Tree Tour DC author and naturalist, Melanie Choukas-Bradley, leads a guided hike on the US Capitol grounds during the 2018 City Nature Challenge. © Bridget Moynihan / TNC
View of the front of the US Capitol building through the branches of a cherry tree. The branches are covered with dark pink blossoms.
City Nature Challenge A dogwood in bloom during a guided hike of the US Capitol grounds during the 2018 City Nature Challenge. © Bridget Moynihan / TNC
× Three children face a tall green bush examining the thick leaves. They are each holding long handled butterfly nets.
× Macro, upside-down view of a brown spider crawling on a ceiling.
× A night photo with flash of a small rabbit sitting in a suburban front yard. The rabbit is sitting on a bare patch of dirt next to a wide concrete sidewalk.
× View looking up through a shallow plastic container of a four-legged winged insect. The insect has a thin body and nearly translucent wings.
× Eight segments of fungus on the bark of a tree. The segments are shaped like fans with brown and white stripes.
× Two women stand on opposite sides of a large tree trunk, smiling and posing while hugging the tree.
× Twelve people gather around a woman during a guided hike in the city. The woman is crouched down in front of a child describing the leaf she is holding.
× View of the front of the US Capitol building through the branches of a cherry tree. The branches are covered with dark pink blossoms.

EXPLORE YOUR WORLD

There are many ways to look for nature in your home or backyard. Discover the plants that are growing on their own and the insects and pollinators that live in and around our homes and yards. You never know what you mind find!

HOW TO FIND INSECTS

Insects are probably some of the easiest organisms to find in and around our homes, since they’re abundant and incredibly diverse! But where should you look to find them? What can you use to catch them?

These sites provide some guidance on how to find and temporarily hold insects. Be sure to release them after you've posted your observation on iNaturalist!

MOTH LIGHTING

Setting up a light and a sheet to attract moths is a simple and easy way to bring more nature into your backyard. Photographing moths on the sheet is easy, and you’ll definitely attract other flying insects as well!

Science Friday has a great set of instructions for observing moths, and the California Center for Natural History has instructions for building your own moth light to attract a wider variety of moths.

How You Can Take Part

What began in 2016 as a friendly challenge between Los Angeles and San Francisco organized by the California Academy of Sciences and the Natural History Museum of Los Angeles County, has now grown to an international event. And it's never too early to start honing your observation skills!

It’s easy to get involved using the iNaturalist app (free on the app store). Just take a picture of a plant or animal and upload it to the app. Our photo gallery of local TNC preserves and partner sites below will help get you started, but you can also explore your own backyard or neighborhood parks. There's nature all around you!

Take a Closer Look

White water rushes over large rocks to create a series of short falls on the Potomac River. Fog rises from the water in the early morning obscuring the tree lined banks.
Potomac Gorge / Bear Island From Great Falls to Georgetown, this 15-mile section of the Potomac River is one of the most ecologically significant natural areas within our entire National Park System. © Roy Sewall
View looking out over a wide, flat valley. The tops of green trees are visible in the foreground. Small farms and communities are in the background stretching to the horizon.
Sugarloaf Mountain Just a few hours from DC, Sugarloaf Mountain has long been a draw for birders in the Mid-Atlantic region. © Kathryn Arion / The Nature Conservancy
A small yellow songbird with black wings perches on a tree branch.
Robinson Neck Preserve The preserve is a birder's delight, where one finds undisturbed waterfowl habitat and a sanctuary for bald eagles. © Becky Stowe/The Nature Conservancy
A small gray-brown fox squirrel stands on a fallen log. The tip of its nose touches a red blossom growing on a brown woody stem.
Third Haven Woods Third Haven Woods provides habitat for a small population of the Delmarva fox squirrel, a recovering endemic subspecies that has been federally listed since 1973. © Dave Spier
Close view of a small canvas being painted in the open air. The canvas shows an open wetland scene. A hand holds a brush adding color to the sky.
Choptank Wetlands The Smithsonian Institution survey ranked this marsh system as one of the most important Chesapeake Bay natural areas. This preserve is accessible only by canoe or kayak. © Mark Godfrey / TNC
Seven people stand at the edge of a wetland during a nature walk. The wide still lake is covered with floating plants. Several people are taking pictures using 35 mm cameras and cell phones.
Oxbow Lake It is easy
 to find gnawed stumps made by beavers throughout the area. Easy to moderate trails allow you to explore the preserve. © Bridget Moynihan / TNC
White water rushes over large rocks to create a series of short falls on the Potomac River. The river bank is thickly lined with trees.
Great Falls Park Managed by the National Park Service, the park is 15 miles from Washington, DC. Throughout the year, over 150 different species of birds can be seen. © Devan King / TNC
A yellow and green square plastic trail blaze is nailed to the trunk of a tree. Three people are seen from behind walking along a trail.
Fraser Preserve Fraser Preserve boasts move than 100 species of birds. The terrain slopes down to the Potomac River, which forms the preserve's northern boundary. © Glenna Goldman / TNC
× White water rushes over large rocks to create a series of short falls on the Potomac River. Fog rises from the water in the early morning obscuring the tree lined banks.
× View looking out over a wide, flat valley. The tops of green trees are visible in the foreground. Small farms and communities are in the background stretching to the horizon.
× A small yellow songbird with black wings perches on a tree branch.
× A small gray-brown fox squirrel stands on a fallen log. The tip of its nose touches a red blossom growing on a brown woody stem.
× Close view of a small canvas being painted in the open air. The canvas shows an open wetland scene. A hand holds a brush adding color to the sky.
× Seven people stand at the edge of a wetland during a nature walk. The wide still lake is covered with floating plants. Several people are taking pictures using 35 mm cameras and cell phones.
× White water rushes over large rocks to create a series of short falls on the Potomac River. The river bank is thickly lined with trees.
× A yellow and green square plastic trail blaze is nailed to the trunk of a tree. Three people are seen from behind walking along a trail.

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