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Glowing Waterdogs and Farting Rivers: A Duke Forest Research Tour

Jonny Behrens looks for aquatic macroinvertebrates with Duke Forest Research Tour participants.

“Who would be surprised if I told you that rivers fart?”

Nick Marzolf, Ph.D., went on to explain that streams release greenhouse gases from decaying matter and gas-producing bacteria. This revelation was one of several new facts I learned at the annual Duke Forest Research Tour in December.

“First and foremost,” says Duke Forest Senior Program Coordinator Maggie Heraty, “the Duke Forest is a teaching and research laboratory.” The Office of the Duke Forest hosts an annual Research Tour to showcase research activities and connect to the wider community. “Connecting people to science and nature, and demystifying scientific research, is a key part of our goals here,” Heraty says.

Duke Forest, which consists of over 7,000 acres in  Durham, Orange, and Alamance Counties, lies within the Cape Fear and Neuse river basins, two of seventeen river basins in North Carolina. What exactly is a river basin? Heraty quoted a poetic definition from North Carolina Environmental Education:

“A river basin encompasses all the land surface drained by many finger-like streams and creeks flowing downhill into one another and eventually into one river, which forms its artery and backbone. As a bathtub catches all the water that falls within its sides and directs the water out its drain, a river basin sends all the water falling within its surrounding ridges into its system of creeks and streams to gurgle and splash downhill into its river and out to an estuary or the ocean.”

Located within the Cape Fear River Basin, the headwaters of New Hope Creek, which passes through the Korstian Division of Duke Forest, are fed by roughly 33,000 acres of land, over 5,000 of which are in the Duke Forest. Land outside of the Forest is of vital importance, too. Duke Forest is working in partnership with other local conservation organizations through the Triangle Connectivity Collaboration, an initiative to connect natural areas, create wildlife corridors, reduce habitat fragmentation, and protect biodiversity in the Triangle region.

New Hope Creek in the Korstian Division of the Duke Forest.

Dwarf waterdogs

We walked down a short trail by the creek, and the tour split into two groups. Our group walked farther along the stream to meet two herpetologists studying the elusive dwarf waterdog.

Bryan Stuart, Ph.D., Research Curator of Herpetology at the North Carolina Museum of Natural Sciences, and Ron Grunwald, Ph.D., Duke University Senior Lecturer Emeritus, are involved in a study looking for dwarf waterdog salamanders (Necturus punctatus) in New Hope Creek. Dwarf waterdogs are paedomorphic, Stuart said, meaning they retain larval characteristics like external gills and a flat tail throughout their lives. In fact, the genus name Necturus means “tail swimmer” in reference to the species’s flat tail.

According to Stuart, on October 3, 1954, Duke professor and herpetologist Joe Bailey collected a dwarf waterdog in New Hope Creek. It was the first record of the species in Orange County.

The Duke Forest is in the westernmost part of the species’ Piedmont range, though it extends farther west in parts of the sandhills. “To have a dwarf waterdog record in Orange County—that’s almost as interesting as it gets,” Stuart said.

Ron Grunwald and Bryan Stuart discuss dwarf waterdog research at New Hope Creek.
Photo provided by The Office of the Duke Forest.

In the late 1960s, Michael A. Fedak, Bailey’s graduate student, did a thesis on dwarf waterdogs in the area. His specimens are still stored in the collections of the North Carolina Museum of Natural Sciences.

No one had studied this population since—until now.

Dwarf waterdogs are very sensitive to pollution and habitat disturbance, Stuart said, on top of the fact that New Hope Creek is already at the edge of the species’s habitat. When Fedak studied them several decades ago, the salamanders were abundant. Are they still?

Stuart, Grunwald, and other researchers want to find out. “The challenge of salamander biology,” Grunwald said, “is that it always happens when it’s freezing.” Surveying salamander populations, he explains, isn’t like watching birds or counting trees. It requires you to go where the salamanders are, and for dwarf waterdog research, that means dark, cold streams on nights when the water temperature is below 55 degrees Fahrenheit.

Researchers bait funnel traps with chicken liver or cat food and set them underwater overnight. Sometimes they catch crayfish. Sometimes they catch nothing. And sometimes they catch exactly what they’re hoping to find: the elusive dwarf waterdog. After all this time, these slippery, nocturnal, chicken-liver-loving salamanders are still here.

Two dwarf waterdogs in a funnel trap before being released back into New Hope Creek.

Though the traps have been successful at capturing some individuals, they will never catch them all, so researchers calculate the recapture rate to estimate the total population. Imagine a bag of rice, Grunwald said. You could count each individual grain, but that would be challenging and time-consuming. Alternatively, you could pull out one grain of rice, color it, and put it back in the bag, then estimate the total number by calculating the probability of pulling out the same colored grain of rice again. In a very small bag, you might draw the same rice grain several times. But the more rice you have, the less likely you are to draw the same grain twice.

To figure out if any of the dwarf waterdogs they catch are recaptures, the researchers mark each individual with a visual implant elastomer, which is “just a fancy way of saying rubber that we can see,” Grunwald said. The material is injected under a salamander’s “armpit” with a small syringe, creating a pattern visible under ultraviolet light. With two colors (fluorescent yellow and red) and four possible injection locations (one behind each leg), there are plenty of distinct combinations. Grunwald showed us a waterdog that had already been marked. Under a UV flashlight, a spot just below its right foreleg glowed yellow.

Captured dwarf waterdogs are injected with a special rubber material that glows under a UV light. Each salamander is marked with a distinct pattern so researchers can recognize it if it’s ever recaptured.

Establishing a recapture rate is essential to predicting the total population in the area. The current recapture rate? Zero. The sample size so far is small—about a dozen individuals—and none of them have been caught twice. That’s an obstacle to statistical analysis of the population, but it’s good news for the salamanders. Every new individual is one more dwarf waterdog survivor in New Hope Creek.

Ron Grunwald with Research Tour participants looking at dwarf waterdogs in bags.
Photo provided by The Office of the Duke Forest.

Stream health

Next, at a different spot along the stream, we met Nick Marzolf, Ph.D., a postdoctoral scholar, and Jonny Behrens, a Ph.D. student, to learn more about New Hope Creek itself. Marzolf and Behrens have both been involved with aquaterrestrial biogeochemistry research in the lab of Emily Bernhardt, Ph.D., at Duke University.

Nick Marzolf (right) and Jonny Behrens discuss stream health.
Photo provided by The Office of the Duke Forest.

Protecting New Hope Creek requires understanding individual organisms—like dwarf waterdogs—but also temperature, precipitation, oxygen levels, pesticide runoff, and biodiversity overall. When humans get stressed, Behrens said, different organs have different physiological reactions. Similarly, different organisms in a stream play different roles and respond to stress in different ways.

Jonny Behrens and Research Tour participants look at aquatic macroinvertebrate samples.
Photo provided by The Office of the Duke Forest.

Behrens passed around vials containing aquatic macroinvertebrates—specimens big enough to see with the naked eye—such as the larvae of mayflies, crane flies, stoneflies, and dragonflies. They are known for being good indicators of stream health because there are many species of macroinvertebrates, and they have different tolerances to stressors like pollution or changes in water temperature.

Aquatic macroinvertebrates can indicate the health of a stream through their species diversity and abundance.
Photo provided by The Office of the Duke Forest.

The water downstream of a nearby wastewater treatment plant is much warmer in winter than other waterways in the area, so researchers see more emergent adult midges and caddisflies there than they do here. Aside from temperature, organisms need to adapt to other changing conditions like oxygen levels and storms.

“Rain is really fun to watch in streams,” Behrens said. The water level rises, pulling up organic matter, and sand bars change. You can tell how high the water got in the last storm by looking for accumulated debris on trees along river banks.

Farting rivers and the peanut butter cracker hypothesis

Marzolf studies hydrology, or “how water moves through not only the landscape but also the river itself.”

Nick Marzolf demonstrates a technique to measure gasses in streams using a syringe.

Part of his research involves measuring gases in water. Streams, like cars and cows and people, release greenhouse gases, including carbon dioxide and methane. In fact, Marzolf and colleagues hypothesize that New Hope Creek contributes more CO2 to the atmosphere per unit area than anywhere else in the Duke Forest.

Decaying matter produces CO2, but that isn’t the only source of greenhouse gasses in the creek. Microscopic organisms, like methane-producing bacteria, produce gases as well.

The “peanut butter cracker hypothesis,” Marzolf said, compares organic matter such as leaves to a cracker, while the “peanut butter,” which makes the cracker more palatable, is the microbes. Scrumptious.

Disturbing the sediment at the bottom of New Hope Creek causes bubbles to rise to the surface due to the metabolic activities of gas-producing bacteria.

Marzolf turned to Behrens. “Do you want to walk around and see if you can stir up some methane bubbles?” Behrens waded into the stream, freeing bubbles from the pressure of the overlying water keeping them in leaf mats. We watched the bubbles rise to the surface, evidence of the activities of organisms too small to see.

Behrens walks around in New Hope Creek to stir up gas bubbles from aquatic bacteria.

Restoring a stream to protect its pigtoe

Finally, Sara Childs, Executive Director of the Duke Forest, discussed stream restoration projects. Though structures in the Duke Forest like remnants of old mills and dams can alter and damage ecosystems, they can also have historical and cultural significance. Duke Forest prioritizes restoration projects that have meaningful ecological, teaching, and research benefits while honoring the history of the land.

For instance, the Patterson Mill Dam was built in the late 1700s and probably remained in use for about 100 years. The stream has already adapted to the structure’s presence, and there isn’t necessarily ongoing degradation because of it. Duke Forest restoration projects, Childs said, don’t revolve around very old structures like the Patterson Mill Dam. Instead, they are planning to remove two more recent structures that are actively eroding banks, threatening wildlife habitat, and creating impounded, oxygen-poor areas in the stream.

One of the structures they are hoping to remove is a concrete bridge that’s endangering a threatened freshwater mussel species called the Atlantic pigtoe (Fusconaia masoni). Freshwater mussels, according to Childs, require a fish species to host the developing mussel larvae on their gills, and the Atlantic pigtoe favors the creek chub (Semotilus atromaculatus). The concrete bridge forms a barrier between the pigtoe and the chub, but removing it could reunite them.

Before starting construction, they will relocate as many mussels as possible to keep them out of harm’s way.

New Hope Creek, home to waterdogs and pigtoe and farting microbes, is precious to humans as well. Heraty describes it as “a really spectacular and beautiful waterway that we are lucky to have right in our backyards here in Durham.”

Post by Sophie Cox, Class of 2025

Bolivia’s Lithium is Like White Gold in the Salar de Uyuni

As the world undergoes the great energy transition — from fossil fuels to alternative energy and batteries — rare earth metals are becoming more precious.

Open The Economist, Forbes, or Fortune, and you’ll see an article nearly every day on Lithium, Nickel, or Copper. For investors seeking to profit off of the transition, lithium seems like a sure bet. Dubbed “white gold” for electric vehicles, the lightweight metal plays a key role in the cathodes of all types of lithium-ion batteries that power electric vehicles (EVs). Although EVs produce fewer greenhouse gasses than gas- or diesel-powered vehicles, their batteries require more minerals, particularly lithium. 

On Sept. 26, Duke’s campus welcomed the first in a series of discussions on climate and energy diplomacy focused on the challenges and opportunities of mining and development in South America’s Lithium Triangle. In a room crowded with curious undergraduate and graduate students alike, some lucky enough to have snagged a seat while others stood at the perimeters, three experts discussed the possible future of Bolivia as a major player in the global lithium market. 

Professor Avner Vengosh of the Nicholas School

Duke Distinguished Professor Avner Vengosh, Nicholas Chair of Environmental Quality in the Nicholas School of the Environment, began by highlighting the staggering EV growth in 2020-2022: Sales of electric cars have more than tripled in three years, from around 4% of new car sales in 2020 to 14% in 2022. That number is expected to rise to 29.50% in 2028. Speaking of the critical element to EV production, lithium, Vengosh said frankly, “we don’t have enough.” 

Lithium is mined from two major sources, Vengosh explained. The first is from hard-rock pegmatite, where lithium is extracted through a series of chemical processes. Most of these deposits are found in Australia, the world’s biggest source. The second is from lithium-rich brines, typically found in Argentina, Bolivia, and Chile, also known as the “Lithium Triangle.” These brine deposits are typically found in underground reservoirs beneath salt flats or saltwater lakes. The Salar de Uyuni in Bolivia is the world’s largest salt lake, and the largest lithium source in the world. It stretches more than 4,050 square miles and attracts tourists with its reflective, mirror-like surface. 

Mountains surrounding the Uyuni salt flat during sunrise By Diego Delso, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=47617647
Mountains surrounding the Uyuni salt flat during sunrise, (Diego Delso)

A group of Duke students led by a PhD candidate pursuing research on Bolivian lithium development recently traveled to Bolivia to understand different aspects of lithium mining. They asked questions including: 

  • How renewable is the lithium brine? 
  • Are there other critical raw minerals in the lithium-rich brines? 
  • What are the potential environmental effects of lithium extraction?
  • What is the water footprint of the lithium extraction process?
  • Is water becoming a limiting factor for lithium production?

The Duke team conducted a study with the natural brine in the Salar, taking samples of deep brines, evaporation ponds, salts from evaporation ponds, wastewaters, and the lithium carbonate. Vengosh said that “we can see some inconsistency in the chemistry of the water that is flowing into the chemistry of the brine.”

This indicates that there is a more complex geological process in the formation of the brine than the simple flow of water into the lake. The team also confirmed the high purity of the lithium carbonate product and that there are no impurities in the material. Additionally, the Duke team found that the wastewater chemistry produced after lithium carbonate production is not different from that of the original brines. Thus, there are no limitations for recycling the water back to the Salar system.

After Vengosh shared the findings of the Duke research team, Kathryn Ledebur, director of the Andean Information Network (AIN) in Cochabamba, Bolivia and Dr. Scott MacDonald, chief economist at Smith’s Research & Gradings and a Caribbean Policy Consortium Fellow, discussed Bolivia’s lithium policy. With the largest untapped lithium deposits in the world, Bolivia has constructed a pilot plan for their lithium production, but Ledebur highlighted that the biggest hurdle is scaling. Additionally, with a unique prior-consultation system in place between the central government and 36 ethnic and indigenous groups in Bolivia, natural resources are a key topic of concern and grassroots action. Ledebur said, “I don’t see that issue changing any time soon.”

Another hurdle is that Bolivian law requires that the extraction process is controlled by the state (the state must own 51%). Foreign investors have been hesitant to work with the central government, which nationalized lithium in 2008 despite, critics said, lacking much of the necessary technology and expertise. 

Maxwell Radwin, a writer for Mongabay, writes, “Evo Morales, the former socialist president who served from 2006 to 2019, nationalized the industry, promising that foreign interests wouldn’t plunder Bolivia’s natural resources as they had in the past. Instead, he said, lithium would propel the country to the status of a world power. Morales didn’t just want to export lithium, though; he wanted to produce batteries and cars for export. This complicated deals with potential investors from France, Japan, Russia and South Korea, none of which came to fruition because, among other things, they were required to take on YLB (the state-owned lithium company) as an equal partner.”

Ledebur said, “At this point in time, the Bolivian government has signed three contracts… and I think things will fall into place.” 

Naysayers say that the Bolivian government hasn’t done anything to take advantage of the massive market sitting beneath their Salars and that grassroot consultations don’t work. Ledebur said, “I don’t think that it’s perfect, but it’s happening.”

Duke students will return to Bolivia with professor Vengosh next year to conduct more research on the lithium extraction process. Then, they’ll be able to see the effects of this ‘happening’ first-hand. 

By Isa Helton, Class of 2026

New Blogger Isa Helton: Asking AND Listening

When I studied abroad in Paris, France, this summer, I became very familiar with the American tendencies that French people collectively despise. As I sat in a windowless back room of the school I would be studying at in the sixth arrondissement of Paris, the program director carefully warned us of the biggest faux-pas that would make our host families regret welcoming a foreign student into their home and the habitudes that would provoke irritated second glances on the street.

Eiffel Tower and the Seine at dusk
La Seine at dusk with Tour Eiffel.

One: American people are loud. Don’t be loud. We are loud when we talk on the phone, loud putting on our shoes, loud stomping around the Haussmanian apartment built in the 1800s with creaky parquet flooring.

Two: Americans smile too much. Don’t smile at people on the street. No need for a big, toothy grin at every passerby and at every unsuspecting dog-walker savoring the few tourist-free morning hours.

Three: Why do Americans love to ask questions without any intention of sticking around to hear the response? When French people ask you how you’re doing – Comment ça va?– how you slept – Vous-avez bien dormi? – how the meal was – Ça vous a plu? – they stand there and wait for an answer after asking the question. So when Americans exchange a jolly “How are you today!” in passing, it drives French people crazy. Why ask a question if you don’t even want an answer?

This welcome post feels a little bit like that American “How are you today!” Not to say that you, reader, are not a patient, intrigued Frenchman or woman, who is genuinely interested in a response –  I am well-assured that the readers of Duke’s Research Blog are just the opposite. That is to say that the question of “who are you?” is quite complicated to answer in a single, coherent blog post. I will proudly admit that I am still in the process of figuring out who I am. And isn’t that what I’m supposed to be doing in college, anyway?

I can satisfyingly answer a few questions about me, though, starting with where I am from. I’m lucky enough to call Trabuco Canyon, California my home– a medium-sized city about fifteen minutes from the beach, and smack-dab in the middle of San Diego and Los Angeles. Demographically, it’s fairly uninteresting; 68% White, 19% Hispanic, and 8% Asian. I’ve never moved, so I suppose this would imply that most of my life has been fairly unexposed to cultural diversity. However, I think one of the things that has shaped me the most has been experiencing different cultures in my travels growing up.

My dad is a classically-trained archaeologist turned environmental consultant, and I grew up observing his constant anthropological analysis of people and situations in the countries we traveled to. I learned from him the richness of a compassionate, empathetic, multi-faceted life that comes from traveling, talking to people, and being curious. I am impassioned by discovering new cultures and uncovering new schools of thought through breaking down linguistic barriers, which is one of the reasons I am planning on majoring in French Studies.

Perhaps from my Korean mother I learned perseverance, mental strength, and toughness. I also gained practicality, which explains my second major, Computer Science. Do I go crazy over coding a program that creates a simulation of the universe (my latest assignment in one of my CS classes)? Not particularly. But, you have to admit, the degree is a pretty good security blanket.

Why blog? Writing is my therapy and has always been one of my passions. Paired with an unquenchable curiosity and a thirst to converse with people different from me, writing for the Duke Research Blog gives me what my boss Karl Bates – Executive Director, Research Communications – calls “a license to hunt.”

Exclusive, top-researcher-only, super-secret conference on campus about embryonics? I’ll be making a bee-line to the speakers with my notepad in hand, thank you. Completely-sold-out talk by the hottest genome researcher on the academic grapevine? You can catch me in the front row. In short, blogging on Duke Research combines multiple passions of mine and gives me the chance to flex my writing muscles.

Thus, I am also cognizant of the privilege and the responsibility that this license to hunt endows me with. It must be said that elite universities are famously – and in reality – extremely gated-off from the rest of society. While access to Duke’s physical space may still be exclusive, the knowledge within is for anyone’s taking.

In this blog, I hope to dismantle the barrier between you and what can sometimes seem like intimidating, high-level research that is being undertaken on Duke’s campus. I hope to make my blogs a mini bi-monthly revelation that can enrich your intellect and widen your perspective. And don’t worry – when it comes to posing questions to researchers, I plan to stick around to hear the response.

Read my summer blogs from my study abroad in Paris HERE!

Post by Isabella Helton, Class of 2026

Meet Some of the Teams at the Bass Connections Showcase

If you weren’t outside enjoying the sun on Wednesday, April 19, you were probably milling around Penn Pavilion, a can of LaCroix in hand, taking in the buzz and excited chatter of students presenting at the 2023 Fortin Foundation Bass Connections Showcase.

Open floor presentations at the 2023 Bass Connections Showcase

This annual celebration of Bass Connections research projects featured more than 40 interdisciplinary teams made up of Duke faculty, graduate students, undergraduate students, and even partners from other research institutions.

Research teams presented posters and lightning talks on their findings. You might have heard from students aiming to increase representation of women in philosophy; or perhaps you chatted with teams researching physiotherapy in Uganda or building earthquake warning systems in Nepal. Below, meet three such teams representing a wide variety of academic disciplines at Duke.

Building sustainable university-community partnerships

As Bass Connections team member Joey Rauch described, “this is a poster about all of these other posters.” Rauch, who was presenting on behalf of his team, Equitable University-Community Research Partnerships, is a senior double-majoring in Public Policy and Dance. His interest in non-profit work led him to get involved in the team’s research, which aims to offer a framework for ethical and effective university-community research collaboration – exactly what teams do in Bass Connections. The group looked at complicated factors that can make equitable relationships difficult, such as university incentive structures, power dynamics along racial, socioeconomic, and ethnic lines, and rigid research processes.

Senior Joey Rauch with his team’s 2nd-place poster!

Along the lines of rigid research, when asked about what his favorite part of Bass Connections has been, Rauch remarked that “research is oddly formal, so having a guiding hand through it” was helpful. Bass Connections offers an instructive, inclusive way for people to get involved in research, whether for the first or fourth time. He also said that working with so many people from a variety of departments of Duke gave him “such a wealth of experience” as he looks to his future beyond Duke.

For more information about the team, including a full list of all team members, click here.

Ensuring post-radiation wellness for women

From left to right: seniors Danica Schwartz, Shernice Martin, Kayle Park, and Michelle Huang

Seniors Michelle Huang, Shernice Martin, Kayle Park, and Danica Schwartz (all pictured) were gathered around the poster for their team, Promoting Sexual Function and Pelvic Health in Women’s Healthcare.

The project has been around for three years and this year’s study, which looked at improving female sexual wellness after pelvic radiation procedures, was in fact a sister study to a study done two years prior on reducing anxiety surrounding pelvic exams.

As Huang described, graduate students and faculty conducted in-depth interviews with patients to better understand their lived experiences. This will help the team develop interventions to help women after life events that affect their pelvic and sexual health, such as childbirth or cancer treatment. These interventions are grounded in the biopsychosocial model of pain, which highlights the links between emotional distress, cognition, and pain processing.

For more information about the team, including a full list of all team members, click here.

From dolphins to humans

Sophomores Noelle Fuchs and Jack Nowacek were manning an interactive research display for their team, Learning from Whales: Oxygen, Ecosystems and Human Health. At the center of their research question is the condition of hypoxia, which occurs when tissues are deprived of an adequate oxygen supply.

Sophomores Noelle Fuchs and Jack Nowacek

Hypoxia is implicated in a host of human diseases, such as heart attack, stroke, COVID-19, and cancer. But it is also one of the default settings for deep-diving whales, who have developed a tolerance for hypoxia as they dive into the ocean for hours while foraging.

The project, which has been around for four years, has two sub-teams. Fuchs, an Environmental Science and Policy major, was on the side of the team genetically mapping deep-diving pilot whales, beaked whales, and offshore bottlenose dolphins off the coast of Cape Hatteras  to identify causal genetic variants for hypoxia tolerance within specific genes. Nowacek, a Biology and Statistics double-major, was on the other side of the research, analyzing tissue biopsies of these three cetaceans to conduct experiences on hypoxia pathways.  

The team has compiled a closer, more interactive look into their research on their website.

And when asked about her experience being on this team and doing this research, Fuchs remarked that Bass Connections has been a  “great way to dip my toe into research and figure out what I do and don’t want to do,” moving forward at Duke and beyond.

For more information about the team, including a full list of all team members, click here.

Post by Meghna Datta, Class of 2023

One Man’s Death Is Not Another Man’s Science

Geer Cemetary in Durham is one of many burial grounds in America that hold the remains of thousands of Black Americans from the 19th century. There are no records of the people buried there. The process of researching grounds like these as a form of reparations to descendent communities was pioneered by Michael Blakey in the African Burial Ground Project in Lower Manhattan, New York. He is currently the Director of the Institute for Historical Biology at the College of William and Mary.

Dr. Michael Blakey. Image courtesy of Library of Virginia Education

On April 4, Blakey visited Duke as a guest of the Franklin Institute of Humanities, the Department of Classical Studies, the Department of International Comparative Studies, and Trinity College. In attendance to his lecture were students of Classical Studies 144: Principles of Archaeology with Alicia Jimenez, International Comparative Studies 283: Death, Burial, and Justice in the Americas with Adam Rosenblatt, and several graduate students by invitation (and me). His presence was clearly highly anticipated.

I initially approached Dr. Jimenez with my interest in bioarchaeology in January as I was planning my Program II application. She invited me to this seminar, and to lunch with Blakey and the graduate students beforehand. I came prepped with questions on osteopenia and hypertrophy, as well as a map of Brightleaf Square so I wouldn’t get lost (I still got lost) and a few dollars cash for parking (they only took card).

Geer Cemetery, Durham, NC. Image Courtesy of Durham in Plain Sight

For those of you who have ever loved the detective fiction heroine Temperance Brennan, Blakey’s work is for you. He is co-chair of the Commission for the Ethical Treatment of Human Remains through the American Anthropological Association. He was claiming the title of bioanthropologist before it was cool. He wrote a guide for the profession called Engaging Descendant Communities, or, more lovingly, The Rubric. Blakey encourages allowing those descendant communities to guide scientists’ research on human remains. He calls us Homo reminiscens, because what makes us “human” may be our affinity for memorializing our dead as much as it may be our large brains (á la Homo sapiens). “Burial is human dignity,” Blakey announced during the seminar, “Dignity is what we do.”

“Ethical code is not law. It is our greatest responsibility.”

Michael Blakey

After all, science has historically been used to justify the unjust. Bioarchaeology is a famous contributor to the field; the pseudoscience of phrenology was upheld until well into the 20th century, and was originally used as “scientific proof” that people of African descent were lesser than Europeans. It was also cited as a justification for displacing Native Americans from their lands.

During lunch, I was struck by Blakey’s cadence. He had a deep, slow voice and spoke with intention. He ordered the giant pretzel. I never asked my questions; instead, I was swept away by the group’s discussion on ethics–a topic I had no open Safari tabs on. I asked instead why a scientist would choose to guide themselves entirely by a non-expert opinion rather than scientific inquiry; would that not hinder discovery?

The scientific method, as you may recall, starts with asking a question. Rather than gracefully including descendent communities after the paper has been written, Blakey urges scientists to only pursue questions about remains that the descendants wish to answer. The science of death should never be self-serving, he noted. There is no purpose to publishing a paper if it is not in the service of the community that provided the subject. A critical reader may notice that The Rubric is not called The Gospel or The Constitution. Rather than a rule of law, it is a guideline. That’s because ethics is based on the respect of self, of craft, and of others. “Ethical code is not law,” Blakey reminds scientists. “It is our greatest responsibility.”

Geer Cemetary has been the subject of Duke research for years now, from a Story+ program to class field trips. Members of ICS, CLST, and FHHI have been in cooperation with Friends of Geer Cemetary to answer such questions about burial conditions–the attempt at dignity granted to Black residents of Durham by their descendants.


Edit: a previous version of this article had incorrectly stated that the Department of African and African American Studies sponsored Michael Blakey’s lecture.

Post by Olivia Ares, Class of 2025

Warning: Birding Can Change You. Let It.

The Wild Ones, a student organization focused on enjoying and learning about nature, recently went to Flat River Waterfowl Compound to look for birds and my personal nemesis.

I have a nemesis (a bird that defies my searching). Actually, I have several, but I have been preoccupied with this particular nemesis for months.

I have seen an evening grosbeak exactly once, in a zoo, which emphatically does not count. For years, I have been fixated on-and-off (mostly on) with the possibility of seeing one in the wild.

Photo of a male evening grosbeak.
Evening Grosbeak” by sedge23 is licensed under CC BY 2.0.

They have thick, conical beaks. The males are sunset-colored. (But good luck finding one at sunset, even though the first recorded sighting supposedly happened at twilight, hence their name.) I daydream about flocks of them descending on my bird feeders at home or wandering onto Duke’s campus. That hasn’t happened yet (unless it has happened while I have not been watching, an excruciating possibility I will simply have to live with).

Evening grosbeaks usually live in Canada and the northern U.S., but they are known to irrupt into areas farther south. Irruptions often occur in response to lower supplies of seeds and cones in a bird’s typical range, making it possible to predict bird irruptions, at least if you’re the famous finch forecaster. (Fun fact: “irrupt” literally means “break into,” whereas “erupt” means “break out.”)

Breaking news: The grosbeaks are in Durham, and they have been since December. I will wait while you perform any necessary reactions, including screaming, jumping up and down in delight, charging outside because you simply have to go find them right now, or telling me I must be mistaken.

I am not mistaken. There is a flock of evening grosbeaks overwintering at Flat River Impoundment, 11.8 miles from Duke University. I know this because I get hourly rare bird alerts by email, and I have been receiving emails about evening grosbeaks nearly every day for almost three months. Put another way, evening grosbeaks have been actively and no doubt intentionally taunting me for weeks on end.

Adam Kosinski, Wild Ones co-president, with binoculars.

Wild Ones, a student organization I’m involved with, had been thinking of organizing a birding trip. For reasons I will not even attempt to deny, I suggested Flat River Waterfowl Impoundment. Last Sunday, seven undergraduates drove there, armed with field guides and binoculars and visions of evening grosbeaks bursting into sight (okay, maybe that was just me).

Flat River Waterfowl Impoundment.
Photo by Adam Kosinski.

The morning was chilly but sunny. Flat River is a gorgeous, swampy place full of small ponds and stretches of long grass edged with trees. As soon as we got there, we were serenaded with birdsong: the high, musical trill of pine warblers, the haunting coo of mourning doves, lilting Carolina wren songs, and squeaky-dog-toy brown-headed nuthatch calls.

Photo by Adam Kosinski.

It wasn’t long before people got to experience the frustrating side of birding. We were admiring a sparrow in a ditch, trying to guess its identity. Someone pulled out a field guide and flipped through the sparrow section only to turn back to the bird and find it gone. Birds can fly. But fortunately, we’d collectively noticed enough field marks to feel reasonably confident identifying it as a swamp sparrow.

A white-throated sparrow, one of several that was feeding on the buds of this tree. Note the white throat and yellow lores.
Photo by Lydia Cox, Wild Ones member. (We are not related, if you’re wondering.)

We found two other sparrow species later: song sparrows and white-throated sparrows. Sparrows tend to be small, brownish, and streaky, but certain features can help distinguish some of the common species around here. I’m personally not very familiar with the swamp sparrow, but it has a rusty cap and gray face. The song sparrow has brown stripes on its head, extensive streaking on its underside, and a dark spot on its breast. The white-throated sparrow has striking black-and-white stripes on the top of its head, yellow lores on its face (the spot in front of the eye), and yes, a white throat. (Just don’t rely too much on bird names for identification. Red-bellied woodpeckers definitely have red heads but usually only have red bellies if you’re rather imaginative, but beware—they’re still red-bellied, not red-headed woodpeckers. Meanwhile, there are dozens of warblers with yellow on them, but only one of them is a yellow warbler. Nashville warblers only pass through Nashville during migration, and American robins aren’t robins at all.)

A Cooper’s hawk with prey between its talons. Note the gray wings, the red barring on the bird’s underside, the dark bands on its tail, and the red eye.
Photo by Lydia Cox.

We saw Carolina chickadees flitting through trees, an Eastern phoebe doing its characteristic tail-wagging, and a Cooper’s hawk feeding on prey. Then, thrillingly, we spotted a bald eagle soaring through the sky. The bald eagle, America’s national bird since 1782, was in danger of extinction for years, largely due to the insecticide DDT, which made their eggs so thin that even being incubated by their parents could make them crack. However, the bald eagle was removed from the endangered species list in 2007, and populations have continued to increase.

A bald eagle in flight.
Photo by Lydia Cox.

Not long after the eagle sighting, we saw another flying raptor: an osprey. In fact, it must have been a good day for raptors because by the end of our trip we had recorded one osprey, two Cooper’s hawks, three bald eagles, and two red-tailed hawks.

We also saw a lot of birders—perhaps two dozen others, maybe more, not counting our own group. Each time we passed a group going in the opposite direction, I asked them if they’d found the grosbeaks.

A bald eagle nest.
Photo taken with my phone through my binoculars, a technique that is slowly teaching me a modicum of patience.

I think everyone I asked had seen them, and they were all eager to point us in the right direction. Birders like to use landmarks like “by the eagles’ nest” and “the fifth pine on the right” and  “past the crossbills.” We found the eagles’ nest, with help from some of the local birders. We think we found the fifth pine on the right, but there were a lot of pines there, so we’re not sure.

We did not find the red crossbills, another irruptive bird species overwintering here this year. (Crossbills are aptly named. The tips of their mandibles really do cross, which helps them access seeds inside cones.)

Red crossbills, another irruptive bird species, have also been overwintering at Flat River Waterfowl Impoundment, but Wild Ones did not see them.
Red Crossbills (Male)” by Elaine R. Wilson, www.naturespicsonline.com is licensed under CC BY-SA 3.0.

We found the spot where the evening grosbeaks had most recently been seen — just twenty minutes before we got there, according to the people we were talking to. We waited. We scrutinized the pine trees. We watched red-tailed hawks and bald eagles circle high above us. We admired the eagles’ nest, a huge collection of sticks high in a pine tree.

Adam Kosinski and Abby Saks, making sure there were no birds hiding underwater. (They were actually looking at interesting water creatures like crayfish and tadpoles.)

Would you like to guess what we did not find? My nemesis. Because the evening grosbeaks have devious minds and clearly flew all the way to Durham with the sole intent of hiding from me, dodging me, flying away as soon as I approached, and flying back again as soon as I was gone. (No, really. Other people reported them at Flat River that same day, both before and after our trip there.)

From left: Ethan Rehder, Barron Brothers, Sophie Cox, Gurnoor Majhail (Wild Ones co-president), and Lydia Cox.
Photo by Adam Kosinski.

Birding can be intensely frustrating. It can plant images in your mind that will haunt you and taunt you for the rest of your life. Like, for instance, the tiny blue bird I caught a brief glimpse of in the trees one early morning in Yellowstone. For years, I wondered if it could have been a cerulean warbler, but cerulean warblers don’t live in the western U.S. Or let’s talk about the green bird—yes, I swear it was green; no, I can’t prove it—that came to my bird feeders several years ago and never came back. Not while I was watching, anyway. The only thing I can think of for that one is a female painted bunting, but painted buntings aren’t usually in upstate South Carolina. (If my local volunteer eBird reviewer in South Carolina ever happens to read this, I promise I won’t report either of those mystery sightings to eBird.) Or, of course, the evening grosbeaks that flew away twenty minutes before we arrived.

Birding can also be thrilling, meditative, and by all accounts wonderful. Yes, that little blue bird in Yellowstone and the maybe-green one in my backyard are branded in my memory, as are countless more moments of maybe and almost and what if? I will never know what they were. I will probably never get over it.

But there are other moments that stick in my mind just as clearly. The bald eagle soaring above us on this Wild Ones trip. The black-capped chickadee that landed on my finger years ago while my brother and I rested our hands on a bird feeder and waited to see what would happen. My first glimpse of a black-throated blue warbler (I am so proud of whoever named that bird species), chasing an equally tiny Carolina chickadee in my backyard.

Warbler illustrations by James Ellsworth De Kay, a zoologist who described hundreds of animal species in the 19th century. From top to bottom: black-throated blue warbler, Cape May warbler, and Nashville warbler.
131. The Black-throated Blue Warbler (Sylvicola canadensis) 132. He Cape-May Warbler (Sylvicola maritima) 133. The Nashville Warbler (Syvicola ruficapilla) illustration from Zoology of New york (1842 – 1844) by James Ellsworth De Kay (1792-1851).” by Free Public Domain Illustrations by rawpixel is licensed under CC BY 2.0.

The Cape May warbler I saw with a close friend in a small field covered in purple wildflowers. The first time I heard the loud, ringing Teacher-teacher-teacher! song of the ovenbird. A blackpoll warbler, the first I’d ever seen, in a grove of trees in a swampy field that only birders seem to find reason to visit.

The moment two Carolina wrens took food from my hand for the first time. Prothonotary warblers (another nemesis bird) practically dripping from the trees on a rainy, buggy hike along a boardwalk. The downy woodpecker that landed on my gloved hand, apparently too impatient to wait for me to finish what I was doing with the suet feeder, and pecked at the suet with that sharp beak, her black tongue flicking in and out, her talons clinging to me with a trust that brought tears to my eyes.

Birding can change you. It can make your world come alive in a whole new way. It can make traveling somewhere new feel all the more magical — a new soundscape, new flashes of colors and patterns, a new set of beings that make a place what it is. In the same way, birding can make home feel all the more like home. Even when I can’t name all the birds that are making noise in my yard, there is a familiarity to their collective symphony, a comforting sense of “You are here.” I encourage you to watch and listen to birds, too, to join the quasi-cult that birding can be, to trek through somewhere wet and dark when the sky is just beginning to lighten—or to simply step outside, wherever you are, and listen and watch and wait right here and right now. You don’t even need to know their names (though once you start, good luck stopping). And you certainly don’t need a nemesis bird. In fact, your birding experience will be calmer without one. But that might not be up to you, in the end. Nemesis birds have minds of their own.

Post by Sophie Cox, Class of 2025

Recovery, Resilience, and Coexistence: Nature-based Solutions on the Coast

When it comes to balancing the needs of humans and the needs of nature, “Historically it was ‘develop or conserve’ or ‘develop or restore,’” says Carter Smith, Ph.D., a Lecturing Fellow in the Division of Marine Science & Conservation who researches coastal restoration.

However, according to Brian Silliman, Ph.D., Rachel Carson Distinguished Professor of Marine Conservation Biology, “We are having a new paradigm shift where it’s not just… ‘nature over here’ and ‘humans over here.’”

Instead, conservation initiatives are increasingly focusing on coexistence with nature and ecological resilience, according to this panel discussion of marine science experts during Duke Research and Innovation Week 2023.

Nature-based solutions — protecting and restoring natural shoreline habitats — have a proven role in protecting and restoring coastal ecosystems. According to the International Union for Conservation of Nature (IUCN), “Nature-based solutions… address societal challenges effectively and adaptively, simultaneously benefiting people and nature.”

The panel, moderated by Andrew J. Read, Ph.D., Stephen A. Toth Distinguished Professor of Marine Biology and Professor of Marine Conservation Biology, also included Brian Silliman, Carter Smith, and Stephanie Valdez, a Ph.D. Student in Marine Science & Conservation.

Living shorelines can help protect coastal ecosystems from storms while also offering benefits for climate and conservation. Photos by Carter Smith.

According to Smith, nature-based solutions can “leverage nature and the power of healthy ecosystems to protect people” while also preserving biodiversity and mitigating climate change. She spoke about living shorelines as an effective and ecologically responsible way to protect coastal ecosystems.

“The traditional paradigm in coastal protection is that you build some kind of hard, fixed structure” like a seawall, Smith said, but conventional seawalls can have negative effects on biodiversity, habitats, nutrient cycling, and the environment at large. “In this case, coastal protection and biodiversity really are at odds.”

After multiple hurricanes, living shorelines had significantly less visible damage or erosion than sites with conventional hardscape protection, like seawalls.

Nicholas Lecturing Fellow Carter Smith

That’s where living shorelines come in. Living shorelines incorporate plants and natural materials like sand and rock to stabilize coastal areas and protect them from storms while also creating more natural habitats and minimizing environmental destruction. But “if these structures are actually going to replace conventional infrastructure,” Smith says, it’s important to show that they’re effective.

Smith and colleagues have studied how living shorelines fared during multiple hurricanes and have found that living shorelines had significantly less “visible damage or erosion” compared to sites with conventional storm protection infrastructure.

After Hurricane Matthew in 2016, for instance, both natural marshes and conventional infrastructure (like seawalls) lost elevation due to the storm. Living shorelines, on the other hand, experienced almost no change in elevation.

Smith is also investigating how living shorelines may support “community and psychosocial resilience” along with their benefits to biodiversity and climate. She envisions future community fishing days or birdwatching trips to bring people together, encourage environmental education, and foster a sense of place.

PhD student Stephanie Valdez then spoke about the importance of coastal ecosystems.

Blue carbon ecosystems,” which include sea grasses, marshes, and mangroves, provide services like stabilizing sediments, reducing the destructive force of powerful waves, and storing carbon, she said. These ecosystems can bury carbon much faster than terrestrial ecosystems, which has important implications when it comes to climate change.

In the atmosphere, carbon dioxide and other greenhouse gasses contribute to global warming, but plants pull carbon dioxide out of the air during photosynthesis and convert it to carbohydrates, releasing oxygen as a byproduct. Therefore, ecosystems rich in fast-growing plants can serve as carbon sinks, reducing the amount of atmospheric carbon, Valdez explained.

Unfortunately, blue carbon ecosystems have suffered significant loss from human activities and development. We’ve replaced these wild areas with farms and buildings, polluted them with toxins and waste, and decimated habitats that so many other creatures rely on. But given the chance, these places can sometimes grow back. Valdez discussed a 2013 study which found that seagrass restoration led to a significantly higher carbon burial rate within just a few years.

Sea grasses, marshes, and mangroves provide services like stabilizing sediments, reducing the destructive force of powerful waves, and storing carbon.

PhD Student Stephanie Valde

Valdez also talked about the importance of recognizing and encouraging natural ecological partnerships within and between species. Humans have taken advantage of such partnerships before, she says. Consider the “Three Sisters:” beans, corn, and squash, which Native Americans planted close proximity so the three crops would benefit each other. Large squash leaves could provide shade to young seedlings, beans added nitrogen to the soil, and cornstalks served as a natural beanpole.

Recognizing that mutualistic relationships exist in natural ecosystems can help us preserve habitats like salt marshes. Valdez points to studies showing that the presence of oysters and clams can positively impact seagrasses and marshes. In restoration, it’s important “that we’re not focusing on one species alone but looking at the ecosystem as a whole”—from top predators to “foundation species.”

“There is hope for successful restoration of these vital ecosystems and their potential to aid in climate change mitigation,” Valdez said.

Finally, Prof. Brian Silliman discussed the role of predators in wider ecosystem restoration projects. Prioritizing the protection, restoration, and sometimes reintroduction of top predators isn’t always popular, but Silliman says predators play important roles in ecosystems around the world.

“One of the best examples we have of top predators facilitating ecosystems and climate change mitigation are tiger sharks in Australia,” he says. When the sharks are around, sea turtles eat fewer aquatic plants. “Not because [the sharks] eat a lot of sea turtles but because they scare them toward the shoreline,” reducing herbivory.

However, Silliman said it’s unclear sometimes whether the existence of a predator is actually responsible for a given benefit. Other times, though, experiments provide evidence that predators really are making a difference. Silliman referenced a study showing that sea otters can help protect plants, like seagrasses, in their habitats.

Restoring or reintroducing top predators in their natural habitats can help stabilize ecosystems impacted by climate change and other stressors.

And crucially, “Predators increase stress resistance.” When physical stressors reach a certain point in a given ecosystem, wildlife can rapidly decline. But wildlife that’s used to coexisting with a top predator may have a higher stress threshold. In our ever-changing world, the ability to adapt is as important as ever.

“I think there is great optimism and opportunity here,” Silliman says. The other speakers agree. “Right now,” Valdez says, “as far as restoration and protection goes, we are at the very beginnings. We’re just at the forefront of figuring out how to restore feasibly and at a level of success that makes it worth our time.”

Restoring or reintroducing top predators in their natural habitats can help stabilize ecosystems impacted by climate change and other stressors.

Brian Silliman

Smith emphasized the important role that nature-based solutions can play. Even in areas where we aren’t achieving the “full benefit of conserving or restoring a habitat,” we can still get “some benefit in areas where if we don’t use nature-based solutions,” conservation and restoration might not take place at all.

According to Valdez, “Previously we would see restoration or… conservation really at odds with academia itself as well as the community as a whole.” But we’re reaching a point where “People know what restoration is. People know what these habitats are. And I feel like twenty or thirty years ago that was not the case.” She sees “a lot of hope in what we are doing, a lot of hope in what is coming.”

“There’s so much that we can learn from nature… and these processes and functions that have evolved over millions and millions of years,” Smith adds. “The more we can learn to coexist and to integrate our society with thriving ecosystems, the better it will be for everyone.”

Post by Sophie Cox, Class of 2025

Rewilding the Gut

Processed foods and overuse of antibiotics can wreak havoc on the trillions of bacteria and other microbes that inhabit the gut. A new study of the gut microbiomes of lemurs looks at whether reconnecting with nature can help restore this internal ecosystem to a more natural state. Credit: Sally Bornbusch.

Modern life messes with the microbiome -– the trillions of bacteria and other microbes that live inside the body. Could reconnecting with nature bring this internal ecosystem back into balance?

A new study suggests it can, at least in lemurs. Led by Duke Ph.D. alumnus Sally Bornbusch and her graduate advisor Christine Drea, the research team collected fecal samples from more than 170 ring-tailed lemurs living in various conditions in Madagascar: some were living in the wild, some were kept as pets, and some were rescued from the pet and tourism industries and then relocated to a rescue center in southwestern Madagascar where they ate a more natural diet and had less exposure to people.

Collecting fecal samples in Madagascar

Then the researchers sequenced DNA from the fecal samples to identify their microbial makeup. They found that the longer lemurs lived at the rescue center, the more similar their gut microbes were to those of their wild counterparts. Former pet lemurs with more time at the rescue center also showed fewer signs of antibiotic resistance.

By “rewilding” the guts of captive animals, researchers say we may be able to better prime them for success, whether after rescue or before translocation or reintroduction into the wild.

This research was supported by grants from the National Science Foundation (1945776, 1749465), the Triangle Center for Evolutionary Medicine, Duke’s Kenan Institute for Ethics, the Margot Marsh Biodiversity Fund and Lemur Love.

CITATION: “Microbial Rewilding in the Gut Microbiomes of Captive Ring-Tailed Lemurs (Lemur catta) in Madagascar,” Sally L. Bornbusch, Tara A. Clarke, Sylvia Hobilalaina, Honore Soatata Reseva, Marni LaFleur & Christine M. Drea. Scientific Reports, Dec. 27, 2022. DOI: 10.1038/s41598-022-26861-0.

Robin Smith
By Robin Smith

Cancer Stigma, Contraceptives, Covid-19: 2022 Global Health Research Showcase

Last Monday, Oct. 17, Duke University students who had conducted global health research had the opportunity to present their work. From North Carolina to Sub-Saharan Africa, the 2022 Global Health Research Showcase featured works that tackle some of the world’s most pressing health issues. Over 40 undergraduate, Masters, and PhD student projects examined a broad range of issues, determinants, and phenomena in countries from almost every continent. Here’s a few project highlights, in case you missed it:

Maeve Salm, pursuing her Master of Science in Global Health, went to Tanzania to study contraceptive use. Tanzania’s youth are highly impacted by teen pregnancy, and Salm wanted to understand desires for contraceptive use among adolescents affected by HIV. She learned that, much like in the U.S., stigma influences access to sexual healthcare for adolescents. This qualitative study aimed to support young people in achieving their desired health outcomes and reducing HIV transmission by examining barriers and facilitators to family planning. Findings indicate that youth agency in reproductive health is of utmost importance.

Maeve Salm presenting her poster at the 2022 Global Health Research Symposium.

Wondering about the Covid-19 response in other countries? Master of Science in Global Health Candidate Stephanie Stan explored the barriers and enablers to the pandemic response in Peru. Per capita, Peru experienced the highest mortality rate form the disease compared to any other country. Due to several challenging factors, they were slow to receive COVID-19 vaccines. However, they implemented highly successful vaccination campaigns once vaccines were obtained. What can be learned from Peru’s pandemic response? Prolonged and proactive collaborations between sectors (healthcare, academics, and government) enable swift public health responses in a crisis. It’s important to have elected officials who are empowered to make decisions promoting science.

“Definitely meeting all the incredible people that I interviewed and learning about their work and involvement in Peru’s pandemic response. Learning about what happens moving forward from their point of view.”

Stephanie Stan, when asked about her global health research experience

Winning the first-place Graduate Student Research Award, Judith Mwobobia’s project examined the stigma of cancer in sub-Saharan Africa. Stigma is a huge barrier to receiving treatment, which is a problem considering that 70% of global cancer deaths originate from Africa. Perceptions of financial stress, misconceptions about cancer, and fear of death were common attitudes driving cancer stigma. Proposed interventions included education and policy recommendations for low-resourced communities. Mwobobia is pursuing her Master of Science in Global Health. Clearly a supportive group, her classmates erupted in cheers when the award was announced.

By Victoria Wilson, Class of 2023

Do Snakes Have Tails? and Other Slithery Questions

Dhruv Rungta, a member of the Wild Ones club, with a ring-necked snake during a herpetology walk with Dr. Nicki Cagle in the Duke Forest.
Upper left: Dr. Nicki Cagle holding a ring-necked snake. Photo by Montana Lee, another Wild Ones member.

On a sunny Friday in September, Dr. Nicki Cagle led a herpetology walk in the Duke Forest with the Wild Ones. The Wild Ones is an undergraduate club focused on increasing appreciation for the natural world through professor-led outings. Herpetology is the study of reptiles and amphibians.

Dr. Cagle is a senior lecturer in the Nicholas School of the Environment at Duke and the Associate Dean of Diversity, Equity, and Inclusion. Along with teaching courses on environmental education and natural history, she is also the science advisor for a citizen science project focused on reptiles and amphibians, or herpetofauna, in the Duke Forest. Volunteers monitor predetermined sites in the Duke Forest and collect data on the reptiles and amphibians they find.

“We get a sense of abundance, seasonality… and how the landscape is affecting what we’re seeing,” Dr. Cagle says. There is evidence that herp populations in the Duke Forest and elsewhere are decreasing.

Dr. Nicki Cagle flipping over a cover board with members of the Wild Ones. The cover boards are used to monitor reptiles and amphibians for a citizen science project in the Duke Forest.

The project relies on transects, “a sampling design… where you have a sampling spot at various intervals” along a line of a predetermined length. In this case, the sampling spots are “traps” meant to attract reptiles and amphibians without harming them. Each site has a large board lying on the ground. “Different herps are more likely to be found under different objects,” Dr. Cagle explains, so the project uses both wooden and metal cover boards.

But why would snakes and other herps want to hide under cover boards, anyway? Reptiles and amphibians are “cold-blooded” animals, or ectotherms. They can’t regulate their own body temperature, so they have to rely on their environment for thermoregulation. Snakes might sun themselves on a rock on cold days, for instance, or hide under a conveniently placed wooden board to escape the heat.

Salamanders that use the cover boards might be attracted to the moist environment, while “snakes will tend to go under cover boards either to hide — like if they’re about to molt and they’re more vulnerable — to look for prey, or just to maintain the proper temperature,” Dr. Cagle says.

Citizen scientists typically check the boards once a week and not more than twice a week. Volunteers have to avoid checking the traps too often because of a phenomenon called “trap shyness,” where animals might start avoiding the traps because they’ve learned to associate them with pesky humans flipping the boards over and exposing their otherwise cozy resting places. By checking the traps less frequently, scientists can reduce the likelihood of that and minimize disturbance to the animals they’re studying.

The first snake we saw was a redbelly snake (Storeria occipitomaculata), dark above with a pink stomach.

Dr. Cagle gave the Wild Ones a behind-the-scenes tour of some of the cover boards. Using a special, hooked tool conveniently stashed in a PVC pipe next to the first cover board, we flipped each board over and looked carefully underneath it for slithery movements. We didn’t find any under the first several cover boards.

But then, under a large sheet of metal, we saw a tiny snake squirming around in the leaf litter. There was a collective intake of breath and exclamations of “snake!”

Dr. Cagle captured it and held it carefully in her hands. Snakes, especially snakes as young as this one, can be all too easily crushed. We gathered around to look more closely at the baby snake, a species with the adorable name “worm snake.” It was dark above with a strikingly pink underside. The pink belly is a key field mark of worm snakes. Earth snakes are also found around here and look similar, but they tend to have tan bellies.

After a minute or two, the worm snake made a successful bid for freedom and wriggled back under the board, disappearing from sight almost immediately.

Crossing over a dry “intermittent stream,” which Dr. Cagle describes as “the running-water equivalent of a vernal pool.” A vernal pool is a temporary wetland that is dry for much of the year.

Some of the cover boards revealed other animals as well. We found a caterpillar chrysalis attached to one and several holes — probably made by small mammals — under another.

Whatever made the holes, we can safely assume it wasn’t a snake. According to Dr. Cagle, the term “snakehole” is misleading. Most snakes don’t make their own holes, though some of them do use existing holes made by other animals. One exception is the bull snake, which is known for digging.

We found a young five-lined skink sunning itself on top of one of the metal cover boards. (Thermoregulation!) Juvenile five-lined skinks are colloquially known as blue-tailed skinks, but the name is somewhat misleading — the adults don’t have blue tails at all.

The snakes we were looking for, meanwhile, were often elusive. Some vanished under the leaf litter before we could catch them. Sometimes it was hard to tell whether we were even looking at a snake at all.

“What are you?” Dr. Cagle muttered at one point, crouching down to get a better look at what was either a stick-esque snake or a snake-esque stick. “Are you an animal? Or are you just a wet something?” (Just a wet something, it turned out.)

The Duke Forest is a valuable community resource with a complicated history. “We know that slavery was practiced on at least four properties” in the Duke Forest, Dr. Cagle says, and the forest is located on the traditional hunting grounds of several indigenous peoples. Today, the Duke Forest is used for research, recreation, timber management, and wildlife management and conservation.

Later on, we found at least three young ring-necked snakes (Diadophis punctatus) under different cover boards. One of them was particularly cooperative, so we passed it around the group. (“All snakes can bite,” Dr. Cagle reminded us, but “some have the tendency to bite less,” and this species “has the tendency not to bite.”) Its small, lithe body was surprisingly strong. The little snake wrapped tightly around one of my fingers and seemed content to chill there. A living, breathing, reptilian ring. That was definitely a highlight of my day.

The faint, dark line on this ring-necked snake’s underside (on the bottom of the loop) is the anal vent. Everything below that point (farther from the head) is considered the official tail of a snake.

If you’ve ever wondered if snakes have tails, the answer is yes. The official cut-off point, Dr. Cagle says, is the anal vent. Everything below that is tail. In between flipping over cover boards and admiring young snakes, we learned about other herps. Near the beginning of our walk, someone asked what the difference is between a newt and a salamander.

“A newt is a type of salamander,” Dr. Cagle says, “but newts have an unusual life cycle where they spend part of their life cycle on land… and that is called their eft phase.” As adults, they return to the water to breed.

We learned that copperheads “tend to be fatter-bodied for their length” and that spotted salamanders cross forest roads in large numbers on warm, rainy nights in early spring when they return to wetlands to breed.

Students holding a ring-necked snake. Above: Kelsey Goldwein (left), Gurnoor Majhail (one of the co-presidents of the Wild Ones), and Simran Sokhi (background on right). Below: Emily Courson (left) and Barron Brothers.

Perhaps the most interesting herp fact of the day came near the end of our walk when one of the students asked how you can tell the sex of a snake. Apparently there are two ways. You can measure a snake’s tail (males usually have longer tails), or you can insert a metal probe, blunted at the end, into a snake’s anal vent. Scientists can determine the sex of the snake by how deep the probe goes. It goes farther into the anal vent if the snake is a male. Why is that? Because male snakes have hemipenes — not two penises, exactly, but “an analogous structure that allows the probe to slide between the two and go farther” than it would in a female snake. The more you know…

Looking for snakes on a herpetology outing with Dr. Cagle and the Wild Ones. Photograph by Gurnoor Majhail.

Disclaimer: Handling wild snakes may result in snake bites. It can also be stressful to the snakes. Furthermore, some snakes in this area are venomous, and it’s probably best to familiarize yourself with those before getting close to snakes rather than afterward. Snakes are amazing, but please observe wildlife safely and responsibly.

Bonus snake! I saw this adorable fellow on the Duke Campus and thought it was an earthworm at first. Dr. Cagle thinks it might be a rough earth snake. I did not check to see if it had a tan belly.
Post by Sophie Cox, Class of 2025

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