Come critter spotting with us on a cold winter's night

In today's episode, host Emily Kwong leads us on a night hike in Patuxent River State Park in Maryland. Alongside a group of naturalists led by Serenella Linares, we'll meet a variety of species with unique survival quirks and wintertime adaptations. We'll search out lichen that change color under UV light and flip over a wet log to track a salamander keeping warm under wet leaves. Emily may even meet the bioluminescent mushrooms of her dreams. Plus, we talk about community events to get outside, such as the City Nature Challenge and Great American Campout. Do you have a question about changes in your local environment? Email a recording of your question to [email protected] mailto:[email protected] — we may investigate it as part of an upcoming Nature Quest segment! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave http://plus.npr.org/shortwave. See pcm.adswizz.com https://pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. NPR Privacy Policy https://www.npr.org/about-npr/179878450/privacy-policy

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

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• 0:19Emily Kwong?

  You're listening to Short Wave from NPR.

• 0:24Emily Kwong?

  What's up, tuterinos? It's Emily Kwong.

• 0:26Speaker 02

  And Burleigh McCoy. Today, I hear you recently embarked on some late night reporting in the woods, under the cover of darkness?

• 0:34Emily Kwong?

  Yeah.

• 0:34Speaker 02

  So is this your way of telling us you're a spy?

• 0:36Emily Kwong?

  Would a spy reveal that?

• 0:38Speaker 02

  OK, my thoughts exactly. But seriously, what were you doing out there?

• 0:42Emily Kwong?

  Well, Burleigh, I was on a night hike.

• 0:45Speaker 03

  So in about two minutes, we'll get started. Meanwhile, enjoy yourself.

• 0:51Emily Kwong?

  It was a tramp through Patuxent River State Park in Maryland, hosted by a group of naturalists, people trained in gathering observations and educating people about the environment. Now, naturalists lead hikes all over the world, but not all of them, like this crew hand out homemade banana bread. That was pretty cool. And UV lights provided by our leader.

• 1:09Speaker 03

  Hi, my name is Serenella Linares. I'm the Facility Director at Noreenier Nature Center and the Program's Chair of the Mycological Association of Washington, DC.

• 1:20Speaker 02

  OK, so Serenella is a mushroom expert?

• 1:24Emily Kwong?

  Yeah, along with other fungi. She's been leading nature walks since 2013. And tonight, I really wanted to see the forest through her eyes, to know what flaps and flutters and fluoresces when the sun goes down in winter.

• 1:38Speaker 03

  It 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 up.

• 1:55Emily Kwong?

  So I should really try to listen very closely to everything.

• 1:58Speaker 03

  We will have a...

• 2:00Emily Kwong?

  And that's what I want to do with you today, Burleigh. I want to just get real quiet and listen to the sounds of a winter's night when everything is dead or dormant, or is it?

• 2:09Speaker 02

  OK, today on the show, we are taking you on a night hike through the Patuxent River watershed in search of owls and salamanders, and maybe, if we're lucky, a bioluminescent mushroom. You're listening to Short Wave, the science podcast from NPR.

• 2:28Speaker 00

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• 3:44Speaker 02

  All right, Emily, so you went on this night hike last month.

• 3:48Emily Kwong?

  Mm-hmm.

• 3:48Speaker 02

  Set the scene for us. What does this park look like?

• 3:52Emily Kwong?

  No idea because it was so dark. And we don't have half of these critters' night vision.

• 3:58Speaker 02

  Okay, this makes sense.

• 3:59Emily Kwong?

  But I know that the park, because I looked at a map, sits along the Patuxent River, which flows into Maryland's Chesapeake Bay. We were bundled in our winter coats and the first stop along our night hike was a patch of lichen growing along a tree just off the parking lot.

• 4:14Speaker 02

  Remind me, what are lichen exactly?

• 4:17Emily Kwong?

  Yeah, lichen is that stuff that grows on trees. It kind of looks like seaweed, but it's actually a hybrid colony of fungi and algae in a symbiotic relationship. To show us, Serenella dramatically shines her flashlight up the tree trunk.

• 4:32Speaker 03

  Nothing out of the ordinary, right? That blue, gray, lichen color. Everything looks pretty much the same.

• 4:45Speaker 05

  Until.

• 4:45Emily Kwong?

  Serenella then flips on her UV light and the patch of green lichen totally changes.

• 4:52Speaker 05

  Want to tell us more about these plants?

• 4:54Emily Kwong?

  And it suddenly glowed neon yellow. The lichen, one particular part of it was fluorescing. So absorbing the ultraviolet light from the flashlight and emitting visible light.

• 5:06Speaker 02

  Oh, and I'm just looking at the pictures you just sent me and this is like neon neon yellow.

• 5:11Emily Kwong?

  Yeah, it was like the Las Vegas strip. Natalie Howe, an ecologist with the US Department of Agriculture, steps forward and shoves her face into the tree bark.

• 5:20Speaker 05

  If you come up real close, you can sort of tell that there's a lot of diversity there because there's some that are a little yellower or some that are a little grayer.

• 5:29Speaker 02

  She sounds so excited.

• 5:31Emily Kwong?

  So we, we take a UV light and get up close to that tree to look and pretty soon Serenella shouts.

• 5:37Speaker 05

  Oh, Natalie.

• 5:41Speaker 05

  What did you find? Oh, orange. That's true. We barely ever see that orange one.

• 5:45Speaker 02

  They just sound so excited. This sounds like my kind of group. Okay, so like what do the different colors mean?

• 5:51Emily Kwong?

  Yeah, okay, so the yellow lichen is called Pyxine subscenaria and the orange lichen is Pyxine ceridiana. And both have chemicals in their tissues which allow them to fluoresce.

• 6:03Speaker 02

  Okay, but like why?

• 6:05Emily Kwong?

  Natalie explained to me that lichen fluoresce as a protective response against ultraviolet light damage from the sun.

• 6:12Speaker 02

  Oh my gosh, I wish we could do this. Okay, that's so cool. So like these lichens are carrying their own sunscreen.

• 6:19Emily Kwong?

  Yep. So the group starts to branch out at this point away from the lichen depot, drifting into pockets of the forest, swinging their UV lights and headlamps up trees. Everyone's kind of getting into it now and they're breaking up books to try to identify what they see. And suddenly it just feels weird to step on anything.

• 6:37Speaker 02

  Because like everything is alive.

• 6:39Emily Kwong?

  Yeah, except where there's trash.

• 6:41Speaker 02

  Oh.

• 6:42Speaker 05

  Oh, once I actually got too excited about finding like a soggy piece of toilet paper. It reflected weirdly.

• 6:48Emily Kwong?

  My gosh. Okay, so what did you see next on your hike? Uh, well, there was this gigantic piece of fabric that one of the naturalists had hung up and lit with mercury vapor lamps. So those are lamps that emit this very broad spectrum of light and attracted all these different kinds of moths, just like clinging to the fabric.

• 7:10Speaker 06

  Come on over here if anyone wants to get a quick photo of the fall canker worm.

• 7:14Emily Kwong?

  I want to see a photo of the fall canker worm. Yeah, this moth, along with all moths, used the moon and stars to navigate. So lamps are a good way to draw them out of the shadows. Um, then Matt Felbrin, a roving naturalist with Nova Parks, the regional park system of Northern Virginia, makes an announcement that he will be, quote, "doing owl calls intermittently." Okay.

• 7:36Speaker 06

  They're very defensive of their territory, so they will frequently come and check out who the potential rival is in their territory.

• 7:44Emily Kwong?

  So what's the best way to call a barred owl?

• 7:47Speaker 06

  There's a mnemonic for it, and the mnemonic would be, "Who cooks for you? Who cooks for you all?"

• 8:00Emily Kwong?

  Matt, Matt learned how to do this while prowling for owls during the Great American Campout. Uh, what is that? It's this nationwide campaign that happens every June to get people outdoors in a safe way. And this was a really common theme among the naturalists. They're all involved with some kind of community work. Anna Kahaniui is the co-founder of the DC-based nonprofit Capital Nature. I found her crouched over a log inches from the dirt, taking a picture with her iPhone. Oh, my gosh. What is that?

• 8:29Speaker 07

  It's a snow fungus, so it's a jelly fungus.

• 8:31Emily Kwong?

  Oh!

• 8:32Speaker 07

  That's, yeah, so I want to get a picture of it.

• 8:33Emily Kwong?

  There's fungi that are jellied?

• 8:36Speaker 07

  Yeah, let me show you a better picture of it.

• 8:38Emily Kwong?

  It looks like slime. So you got Matt making owl calls in the background. Anna, face in the dirt, showing me her iNaturalist.

• 8:45Speaker 02

  Okay, so iNaturalist is that app that helps you ID things in the natural world. I use it all the time for things like flowers and trees and one time a spider in my garden.

• 8:54Emily Kwong?

  Yeah, Anna's like a prolific user of iNaturalist.

• 8:58Speaker 02

  Well, you have 5,107 observations.

• 9:01Speaker 07

  I do make a lot of observations.

• 9:03Speaker 02

  Wow, 5,100, that's a lot.

• 9:06Emily Kwong?

  Yeah, I have, I don't know, a few dozen. But I have realized that learning to identify and name and even just notice the life forms around me is one of the best ways to deepen your relationship to land and to nature. Anna says you can also look up a bird count or some other bio blitz in your area. That's what they call like these nature searches. One of the biggest ones is the City Nature Challenge.

• 9:31Speaker 02

  Oh, what's that?

• 9:32Emily Kwong?

  It's basically a four day sprint around Earth Day. Cities who enroll are tasked with identifying as many of a certain type of species as possible.

• 9:41Speaker 07

  It's multi-generational. So because you know, mom and dad and grandma and grandpa and the kids can go out and the kids are low to the ground, so.

• 9:48Speaker 02

  So did that owl ever show up?

• 9:51Emily Kwong?

  Never showed. Gave us the cold shoulder. But at this point in the hike, owl cameo didn't really matter. I mean, over the course of the night, just watching these grown adults act more and more like kids was so amazing, like sticking their fingers in dirt, rolling over wet logs, jumping and shrieking when a tiny crustacean, like an isopod appeared.

• 10:16Speaker 02

  I love it. Oh no, it's like a little shrimp.

• 10:18Emily Kwong?

  Or a tiny fungi shaped like a fan with an incredible secret.

• 10:22Speaker 03

  Que es a filum commune doesn't have two sexes, doesn't have four sexes. Give me a number of how many sexes do you think?

• 10:32Speaker 02

  Six?

• 10:33Emily Kwong?

  No, higher.

• 10:34Speaker 02

  Twenty-seven?

• 10:36Emily Kwong?

  Goes so much higher than you think is possible for how many sexes an organism can have.

• 10:41Speaker 02

  I mean, 27 was the highest, you know, like what, hundreds?

• 10:45Emily Kwong?

  20,000. This fungi has 20,000 different sexes.

• 10:50Speaker 02

  Amazing.

• 10:51Speaker 03

  It's very successful, very abundant and found almost everywhere. Take a look.

• 10:58Emily Kwong?

  And then there were life forms that were moving quite actively, like.

• 11:02Speaker 07

  We got a salamander? Yep.

• 11:07Emily Kwong?

  So I got low, you know, army crawling and peering through everyone's legs hovering beneath this like chaotic cloud of science facts.

• 11:15Speaker 02

  Yeah, it's like orange and black and slithering. It looks kind of like a snip.

• 11:20Speaker 06

  We have our eastern redback salamander. Yeah. Copperish.

• 11:25Emily Kwong?

  One of the most interesting things I picked up was the fact that redback salamanders will bury themselves, sometimes a foot deep in winter, to basically be surrounded by decaying roots to stay warm and wet because the salamanders need the moisture to absorb oxygen through their skin. Yeah, and there's so many adaptations for winter when you really start to look for them. Sometimes that looks like a change of location, sometimes that looks like energy conservation.

• 11:52Speaker 02

  Okay, give me an example.

• 11:54Emily Kwong?

  Yeah, this was towards the end of the hike. I hear Serenella calling my name in the dark. Oh, all people look the same.

• 12:01Speaker 03

  We don't overlook the stick.

• 12:03Emily Kwong?

  The stick with the mushroom.

• 12:05Speaker 03

  With the mushroom.

• 12:06Speaker 02

  Wait, is this the bioluminescent mushroom?

• 12:08Emily Kwong?

  That's right, that's right. This is the one Serenella spent the whole hike searching for. It is a honey mushroom. Our final observation of the night. So in the summertime, honey mushrooms produce a green light known as fox fire. They glow in the dark all on their own, no flashlight required, and we call this phenomenon bioluminescence.

• 12:28Speaker 02

  I am really sad to say I've never seen bioluminescence in nature, but honestly, I usually imagine it's like a frog or some kind of plankton doing the bioluminescing, not a mushroom.

• 12:40Emily Kwong?

  Yeah, I had no idea that mushrooms bioluminesce either. Scientists don't entirely know why, but as Serenella explained to me and my husband Duncan, it might be the fungi's way of attracting nocturnal creatures. You know, the glow is basically an advertisement saying.

• 12:56Speaker 03

  Come get me, I'm delicious. And by the way, take my kids away. So how do you advertise your Burger King at 2 a.m.? Like, you need a neon sign that people walking by say, oh, yummy.

• 13:16Emily Kwong?

  Hungry animals, so birds, rodents, and insects, eat the mushrooms and poop it out later, which may help with spore dispersal. But that's not what I saw, Burley.

• 13:27Speaker 02

  No?

• 13:28Emily Kwong?

  No, it was winter, and apparently, the honey mushrooms will shut down all bioluminescent business. They will not glow at night in wintertime.

• 13:37Speaker 02

  Bummer. You did not see the green glow.

• 13:41Emily Kwong?

  Nope, just a stick of happy brown caps that were not bioluminescing at all, which I think provides a nice life lesson for wintertime, you know, about not spending energy when you don't have to.

• 13:52Speaker 02

  Honestly, Emily, this hike is reminding me that that's what winter is all about, right? At least according to nature. Slow down, rest, conserve your energy.

• 14:02Emily Kwong?

  And you can consider this hike your permission slip.

• 14:04Speaker 02

  Thank you so much for this night walk.

• 14:07Emily Kwong?

  Anytime, Burley. To join the City Nature Challenge or the Great American Campout, check out the links on our website.

• 14:15Speaker 02

  Make sure you never miss a new episode by following us on the podcasting platform you're listening from. And if you have a science question, send us an email at [email protected]. This episode was produced by Jessica Young and Hannah Chin and edited by our showrunner, Rebecca Ramirez. Tyler Jones checked the facts. Jimmy Keeley was the audio engineer. Beth Donovan is our senior director, and Colin Campbell is our senior vice president of podcasting strategy.

• 14:43Emily Kwong?

  I'm Emily Kwong.

• 14:44Speaker 02

  And I'm Burley McCoy. Thanks for listening to Short Wave from NPR.

• 14:58Speaker 00

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