UTC Assistant Professor Rich Walker and ichthyology students during a March 19, 2025, research excursion to Falling Water Creek to catch and identify fish. Photo by Angela Foster.
During the 2024 cicada emergence, Dr. Rich Walker was knee-deep in research.
Armed with nets, water testing kits and a curiosity about nutrient pulses in freshwater systems, Walker—now an assistant professor in the University of Tennessee at Chattanooga Department of Biology, Geology and Environmental Science—was wading through streams collecting data on fish and their unexpected meals.
A young researcher in the early stages of his academic career, Walker was pursuing an idea that many ecologists hadn’t yet explored in depth: What happens to aquatic ecosystems when cyclical cicadas die by the millions?
“It’s that huge pulse of nutrients and carbon that are coming from below ground to the terrestrial forest ecosystems and then falling into the streams and influencing them,” he said. “No one had really looked at this from the perspective of a macroconsumer such as a fish, so we decided to try and tackle that.”
Walker’s project, titled “The Cicadian Rhythm: Integrated Research And Education To Reveal The Cascading Effects Of A Rare But Massive Terrestrial Resource Pulse In Stream Ecosystem,” is now drawing national recognition. He is one of just 36 early-career faculty members nationwide to be named a 2025 recipient of the Ralph E. Powe Junior Faculty Enhancement Award from Oak Ridge Associated Universities (ORAU), a consortium of over 160 colleges and universities that collaborates with federal agencies to advance health and scientific knowledge.
Biology, Geology and Environmental Science Department Head Gretchen Potts said the award recognition aligns with Walker’s strengths.
“By fostering interdisciplinary collaboration and promoting conservation education, the ORAU Ralph E. Powe Junior Faculty Enhancement Award will allow Dr. Walker to engage undergraduate and graduate students in meaningful and impactful research,” Potts said. “This will enhance the understanding of aquatic-terrestrial connections and strengthen ecology and conservation curricula for underrepresented communities, inspiring students to pursue careers in STEM and supporting effective conservation practices.”
The highly competitive award comes with a $5,000 grant that will help fund Walker’s continuing research and student engagement.
“It feels great. I’m grateful that I was given this opportunity,” said Walker, who earned his Ph.D. in ecology from the University of Wyoming in 2019. He was a faculty member at Upper Iowa University before coming to UTC at the start of the fall 2024 semester.
Walker said part of what lured him to Chattanooga was “the great diversity of aquatic ecosystems and critters that you find here in the Southeast.”
“Tennessee and the Southeast in general are just a biodiversity hotspot for freshwater organisms,” he said. “With over 320 species of fish in the state itself, that was a big draw for me.”
Students in Dr. Rich Walker’s ichthyology course deep in research in Falling Water Creek.
An aquatic ecologist by training, Walker explained that his research focuses on the interconnections between land and stream environments and how stressors—such as climate shifts or chemical changes—affect aquatic species.
The cicada research, he said, first took shape during his time at Upper Iowa. With the rare double brood emergence in 2024—both a 17-year brood and a 13-year brood of the insects—the opportunity to study cicadas’ effect on stream life, especially fish, became too compelling to pass up.
When the broods emerged, Walker and a student research team began surveying sites across four states.
“We traveled through Arkansas, Missouri, Illinois and Iowa collecting cicadas drifting in the stream and collecting fish that were in those streams to see how they were interacting,” he recalled. “How are the cicadas falling into the stream? How many are falling in? Are the fish eating them? Which species are eating them?”
After he moved to Chattanooga, the stream research continued with sampling across Tennessee and Kentucky.
Walker said he and his UTC student researchers now have the opportunity to process data from three different brood emergence events, and—thanks to the ORAU funding—they will add a new experimental component to their work: a streamside mesocosm that simulates cicada decomposition and its ripple effects through microbes, invertebrates and fish.
A mesocosm is an enclosed, controlled outdoor environment that mimics natural conditions, allowing researchers to study ecological processes in a realistic yet manageable setting. In this case, it will enable Walker and his team to isolate and measure how decaying cicadas influence stream ecosystems.
He said the research opportunities for undergraduate and graduate students were a primary reason for pursuing the grant. As part of the hands-on experience, students will contribute to data collection, analysis and presentation.
Walker, who once imagined himself becoming a veterinarian, said his own academic journey took a welcome turn after taking an ichthyology course for fun as an undergraduate at the University of Central Arkansas.
“I realized that, ‘Hey, I could get paid to play outside and catch fish all day,’” he said with a laugh.
Now, he’s helping to shape future scientists. Some will showcase their discoveries at next year’s UTC Spring Research and Arts Conference, while others may submit work to national conferences in ecology or biology.
“I know this will definitely help with their critical thinking skills, their experimental design skills, and improve their communication and networking skills,” he said.
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UTC Biology, Geology and Environmental Science
Dr. Rich Walker brought his ichthyology class to the Tennessee River on March 26, 2025, to catch and identify fish.
