I recently embarked on some late night reporting in the woods under the cover of darkness. And no, I am not a spy.
Through the Mycological Association of Washington D.C., I heard about monthly night hikes offered by a group of naturalists in the D.C. Metro Area.
Led by mycologist Serenella Linares, the group offers hikes to two dozen participants through Patuxent River State Park in Maryland.
Huddled in the parking lot, Linares told us, "This is a night for nature magic: Bioluminescence, fluorescence of fungi and lichens, of insects that fly in the night and are attracted to the bait that we have set out."
Linares has been leading public hikes since 2013 and is Facility Director at the Mt. Rainier Nature Center. Her fellow naturalists handed out UV lights and banana bread and beckoned us forward.
We then ventured into the woods, beneath the full moon.
Located along the upper 12 miles of the Patuxent River, the watershed ecosystem is a haven for wildlife — that's even easier to spot in winter.
"You can't see lichens that well in the nighttime. But they're amazing for winter hikes," said Natalie Howe, an ecologist with the U.S. Department of Agriculture.
Shining her ultraviolet light up a tree, certain parts of the pearly green lichen glowed neon yellow. A particular species of lichen, Pxyine subscinerea, has chemicals in its tissue that allow it to fluoresce. This serves as a protective response against ultraviolet light damage from the sun, almost as if the lichen has built-in sunscreen.
Emboldened by the lichen discovery, the group began to branch out — drifting between pockets of the forest and swinging their headlamps up trees in search of life.
Suddenly, it felt weird to step on anything.
Some critters visited our group through flight. Moths use the moon and stars to navigate, and were drawn to a piece of fabric flooded with mercury vapor lamps.
Matt Felperin, the Roving Naturalist with NOVA Parks, the regional park system of Northern Virginia, spent most of the evening imitating the call of a bard owl.
"There's a mnemonic for it. And the mnemonic would be, 'Who cooks for you? Who cooks for you all?'" he told me as leaves crunched underfoot.
Felperin learned how to summon owls during the Great American Campout, a nationwide campaign every June to get people out into the forest in a safe way.
In fact, all the naturalists leading our night hike were involved in some kind of community outreach program.
Ana Leilani Ka'ahanui is the co-founder of Capital Nature, a non-profit connecting people with nature in the D.C. area. She is also a Certified Forest Therapy Guide. Midway through the night, I found her crouched over a log – inches from the dirt – taking a picture with her iPhone.
She explained how people can upload pictures of wildlife for identification through apps like iNaturalist. Ka'ahanui has used the app to identify over 5,000 species, contributing to biodiversity science through backyard observation.
Between snapping photos of a jelly fungi, she repeatedly emphasized: You do not have to live in a rural area to make observations. "We believe if you help people feel connected to nature, they will protect it and they will be stewards of it."
One of the biggest BioBlitz events is the City Nature Challenge, a four-day sprint around Earth Day. Participants in enrolled cities are tasked with identifying as many of certain types of species as possible.
Ka'ahanui appreciates that the challenge encourages people of all ages to get outdoors. "Mom and dad and grandma and grandpa and the kids can go out. And the kids are low to the ground. So they can see, 'Oh, here's this worm,'" she says.
Fittingly, one salamander, an isopod and a squirrel skull later, Linares led me to our final observation of the evening: a bioluminescent honey mushroom of the genus Armillaria. In the summertime, certain species of Armillaria self-produce a green light known as foxfire.
Scientists call this phenomenon of species self-producing light bioluminescence. The glow may be the fungi's way of attracting nocturnal creatures to consume the mushroom and, through their digestive droppings, aid with spore dispersal.
"How do you advertise you're Burger King at 2 a.m.? You need a neon sign that people walking by say, 'Oh yummy,'" Linares says with a chuckle.
On this winter's night, however, mushroom was not aglow with foxfire. Honey mushrooms often shut bioluminescence down in winter to conserve energy.
I took this as confirmation of nature's lessons — and the wisdom of allowing oneself to rest in winter.
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Today's episode was produced by Hannah Chinn. It was edited by Rebecca Ramirez. Tyler Jones checked the facts. Jimmy Keeley was the audio engineer.
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