Bundled up against the crisp morning air, a group of students watches a distant herd of bison meander across the Yellowstone landscape. They scribble notes—counting calves, identifying age groups, and tracking social behaviors. And then, they wait. Finally, the moment they’ve been anticipating… a bison does its business. Cheers are (quietly) stifled as they mark the spot and patiently watch the herd shuffle along. Once the coast is clear, they move in, carefully scooping up the fresh sample like scientific treasure hunters. This precious poop will soon make its way to Brown University, where researchers will analyze it to uncover insights into bison diet and movement. Science it’s a little messy, but always fascinating!
“I had a lot of fun and was able to experience Yellowstone through a scientific lens. It was my first time camping for this long and I really enjoyed it. Now I see the animals in Yellowstone in a new way because I know so much more about them and their politicized history,” says Fizzy from East Grand Rapids High School.
Since 2016, Ecology Project International (EPI) has participated in the "Home on the Range" project, a long-term study on the ecology of ungulates (hoofed mammals) in Yellowstone. Through citizen science, EPI students have contributed crucial data for species management, reinforcing the connection between conservation, education, and informed decision-making.
Joe Loviska, EPI's Yellowstone Program Manager, explains:
“When EPI got involved, it was a way to practice citizen science in Yellowstone in a really meaningful way. It was an opportunity to contribute directly to the understanding of ungulate ecology in a landscape that is perhaps the best in the Americas for studying their behavior in grassland ecosystems.”
How Does EPI Contribute to Bison Conservation?
Through this program, students participate in bison monitoring, collecting essential data on their behavior, distribution, and diet. This is done through two main protocols:
Demographic studies: observing herds, recording the age, sex, and social structure of bison.
Fecal sample collection: analyzing diet and migrations of the species. The collected data is stored in Yellowstone and later analyzed by Brown University.
This work has led to significant findings, such as the discovery that bison not only follow the "green wave" of plant growth in spring but also create "grazing lawns" that uniquely regenerate grasslands.
“Bison follow the green wave up to a point but then they can also, because of their grazing habits, create grazing lawns… that effectively recreate that wave in place,” Loviska explains.
Studies like these were key in the recent update of Yellowstone’s bison management plan in 2024.
Challenges in Bison Management
Despite their ecological importance, bison management in Yellowstone is a controversial topic. In winter, they seek lower-elevation grasslands outside the park, leading to conflicts with local ranchers concerned about the transmission of the brucellosis virus to cattle. As a result, the state of Montana has implemented different population control methods:
Controlled hunting by indigenous tribes and public hunters: This method is based on long-standing traditions and legal agreements that recognize the hunting rights of indigenous groups. Tribal members participate in these hunts as part of their cultural and subsistence practices, while public hunting is regulated by permits to manage population levels. This approach helps to keep bison numbers within sustainable limits while honoring indigenous sovereignty and traditions.
Capture and relocation to tribal reservations under strict health controls: When feasible, bison are captured and placed in quarantine to ensure they are free of brucellosis before being transferred to tribal lands. This process allows indigenous nations to restore bison populations on their ancestral lands, supporting both ecological and cultural revitalization. However, the quarantine process is lengthy and requires significant resources, limiting the number of bison that can be relocated each year.
Slaughtering bison when the population exceeds the park ecosystem’s carrying capacity: While not the preferred method, slaughter is sometimes necessary when population levels exceed what Yellowstone’s habitat can sustain. Without enough space to migrate naturally, excessive bison numbers can lead to overgrazing and resource depletion. When relocation is not an option, some bison are humanely euthanized, with meat and hides often distributed to indigenous tribes for food and cultural use.
In 2024, the National Park Service (NPS) updated the Bison Management Program, reflecting the latest research and ecological findings. This program ensures that bison management decisions are based on science and involve coordination with federal, state, and tribal entities.
EPI and Bison Restoration on Tribal Lands
One of the most important advances in bison management has been their relocation to indigenous reservations through Yellowstone’s transfer program. Through this process, bison undergo a quarantine period to ensure they are brucellosis-free before being sent to tribal lands across the country.
EPI has also expanded its work to the Fort Peck Reservation in Montana, supporting educational programs on the cultural importance of bison for indigenous communities. Through this effort, EPI not only helps conserve the species but also contributes its grain of sand to strengthens indigenous nations’ sovereignty and their relationship with bison.
Impact on Students
Students participating in EPI’s bison monitoring experience a transformative journey.
“My EPI experience made me really appreciate and achieve deeper understanding of the relationships between all factors of an ecosystem,” says Alex Pollmer from Stuyvesant High School.
Many students highlight how this program changes their perception of science and conservation.
“I used to see science as just a lab and now I know that it’s all around us and you don’t have to be super smart to enjoy it,” says Amelia Weldon from Hunterdon County Vocational School District.
A Future for Bison
Bison monitoring in Yellowstone is a key effort for the conservation of this species and the health of the park’s ecosystem. Through citizen science, EPI not only provides valuable data for management decision-making but also educates new generations and supports bison restoration on tribal lands.
By continuing this work, EPI reaffirms its commitment to conservation, education, and building a future where bison and people can sustainably coexist.
If you or your school are interested in contributing to a project like this, check out our Travel Programs and join us for an unforgettable adventure in the field: https://www.ecologyproject.org/travel-programs