Traces on the range: NREM postdoc uncovers Yellowstone's ecological history
Wednesday, May 21, 2025
Media Contact: Sophia Fahleson | Digital Communications Specialist | 405-744-7063 | sophia.fahleson@okstate.edu
John Wendt, who is a postdoctoral fellow in ecology and environmental sciences at Oklahoma State University, is pushing the boundaries of ecological research with his innovative approach to studying herbivore populations and their impact on ecosystems.
Wendt’s work is advancing the field of paleoecology, which is the study of interactions between organisms and their environments across geologic timescales. His work provides critical insights into ecosystem management essential for conservation efforts across North America, he said.
Wendt, now based in the OSU Department of Natural Resource Ecology and Management, began his journey at Montana State University, where he obtained his doctorate in ecology and environmental sciences and studied the Northern Range of Yellowstone National Park.
The area, known for its large herds of bison and elk, is one of the most ecologically significant regions in the United States, Wendt said.
“If you’ve ever visited Yellowstone and seen herds of bison in grassy valleys, you were probably in the Northern Range,” Wendt said.
The Northern Range, where bison survived near extinction in the late 1800s, remains a critical area for ecological research because of its diverse herbivore populations, Wendt added.
At MSU, Wendt introduced an innovative method to study these populations: coring lake sediments to extract preserved chemical compounds called fecal steroids.
These compounds are molecular traces of herbivore waste that can persist in lake sediments for millennia. This technique allowed Wendt to track herbivore populations and their ecological impacts during the past 2,000 years.
“The goal was to identify and quantify fecal steroids from herbivores like elk, bison, and moose to understand how these populations have changed over time and influenced the landscape,” Wendt said.
In his research at MSU, Wendt discovered grazers, specifically elk and bison were the dominant herbivores in the Northern Range the past two millennia. Their population dynamics reflect both natural changes and the impacts of human management practices, Wendt said.
“One of the most surprising findings was how changing management strategies during the 20th century influenced the herbivore population and its effects on vegetation,” he said.
“Our work highlights the connection between modern wildlife management strategies such as predator control, bison and elk population culling, eventual reintroduction of wolves and historical ecological shifts,” he added.
As a postdoctoral fellow in the OSU Ferguson College of Agriculture, Wendt is continuing his research to gain a deeper understanding of herbivore populations across diverse ecosystems, he said.
“At OSU, I’m working to expand our knowledge beyond Yellowstone by examining herbivore populations in other regions, such as the Great Plains,” Wendt said.
His goal is to understand how herbivore dynamics vary in ecosystems with different ecological and management practices, he added.
Wendt’s work at OSU is further supported by advanced laboratory equipment and collaborative partnerships. Tracy Quan, professor in the OSU Boone Pickens School of Geology, will provide the technical assistance needed to analyze complex organic molecules like fecal steroids.
“Our lab provides the essential equipment for safely analyzing these complex molecules,” Quan said.
“John is the expert on his biomarkers and research area, where my role is to make sure he has the resources and support to carry out his work effectively,” she added.
While Quan’s lab serves crucial support, Wendt remains the driving force behind the project, refining molecular biomarkers and improving ecological models that deepen the understanding of how past herbivore activity relates to current wildlife management strategies, Quan said.
Craig Davis, a professor of wildlife management in the NREM department, is another collaborator on Wendt’s research.
Davis, who specializes in wetlands and range management, is contributing his expertise to inform Wendt’s palaeoecological work.
Davis’ work included a project exploring carbon sequestration in the Nebraska Sandhills, he said, which inspired his collaboration with Wendt.
“We started doing some work on carbon sequestration in the Sandhills, and it got us thinking about how John’s work could lend itself to telling a broader story, whether you’re working in the Sandhills or here in Oklahoma,” Davis said.
Davis sees a deep connection between Wendt’s palaeoecological approach and modern conservation strategies, he said, especially in understanding the historical effects of grazing and fire on landscapes.
“The idea of going back in time is really intriguing to me,” Davis said. “Studying past herbivore impacts gives us the tools to understand how present-day wildlife management strategies help shape ecosystems.”
Though Davis’ role has been more peripheral, he said collaborating with Wendt is fascinating because he has never worked in this type of research.
“This research could add a lot to our knowledge about how ecosystems have been shaped through time and help guide how we might shape them in the future,” Davis said.
Looking ahead, Wendt said he plans to expand his research to more locations in the Northern Range and beyond. He aims to build collaborations to refine methods and broaden the understanding of ecological dynamics, he added.
“We need to cover a broader geographic range to better understand herbivore migration, seasonal usage and the impacts of different management practices,” Wendt said. “My goal is to use palaeoecological methods to uncover details of the history of herbivore-ecosystem interactions, which could ultimately guide more effective conservation strategies across North America.”
Story by Brilee Payne | Cowboy Journal