About Cedar Creek Ecosystem Science Reserve - Cedar Creek Ecosystem Science Reserve is a University of Minnesota biological field station that is world-renowned for its long-term ecological research. Its 5,500 acres includes many ecosystems and species found throughout the forests, grasslands, and wetlands of Minnesota and North America. Faculty, staff, and students who work at Cedar Creek are dedicated to discovering sustainable solutions to environmental challenges. We do this by: (1) investigating the fundamental processes that govern the dynamics and functioning of ecological communities and ecosystems, and how human activities are changing ecosystems; (2) sharing knowledge gained at Cedar Creek with citizens of the state, the nation, and the world through our vibrant education and community engagement programs, as well as through participation in national and international initiatives; and (3) conserving natural ecosystems as platforms for study and as examples of intact ecosystems. Cedar Creek has a long history of ecology research and active research has been conducted within Cedar Creek’s oak savannas since the 1960s.
About the bison at Cedar Creek - Oak savanna is one of Minnesota’s most threatened ecosystems. Today, less than 0.1% of the original savanna remains, and most remnants have lost their native grasses and wildflowers as a lack of fire allows trees to dominate and shade them out.
Savanna restoration research at Cedar Creek started in 1964 and has shown that prescribed fire eliminates shrubs and non-savanna tree species and restores savanna species. However, this research has also shown that these frequent fires are preventing oaks from regenerating. It is now clear that fire, by itself, is leading to the slow loss of savanna because oaks are not replacing themselves.
Grazing by large herbivores like bison may be essential for savanna restoration and preservation as bison preferentially graze the most abundant native grasses. When not grazed, these grasses compete with oak seedlings for water, light and nutrients. When these grasses burn, their high abundance causes intense fires that kill oak seedlings. Bison grazing may promote oak survival by decreasing competition and fire intensity. In the past, bison roamed Minnesota’s oak savannas but have been absent for nearly 200 years. By introducing bison to the oak savannas at Cedar Creek, we hope to better understand how we might preserve Minnesota’s oak savannas long into the future.
To study the effect bison grazing has on oak savannas, researchers at the University of Minnesota set up an experiment funded by Minnesota’s Environment and Natural Resources Trust Fund. Across the savanna at Cedar Creek, this team of scientists created areas where the bison could and could not graze and planted nearly 700 oak trees into these plots. This allows them to study how grazing by bison can reduce competition between the dominant grasses and oak seedlings as well as how grazing can reduce the intensity of fire. Over the coming years, they will study the growth and survival of these oak trees in areas grazed and ungrazed by bison.
On June 13th 2018, Cedar Creek, along with our partners at NorthStar Bison, released a herd of bison at Cedar Creek. The bison are able to roam 200 acres of oak savanna at Cedar Creek. Over the next week, the bison quickly settled in to their summer home, exploring the savanna, grazing, wallowing, and shedding their winter coats by rubbing on trees. NorthStar’s bison were rounded up at the end of the summer and a new herd returned in May 2019. Over the course of the summer, the bison graze the savanna gaining 200 to 300 pounds by the time they leave.
You can visit NorthStar’s Cedar Creek bison this summer on Saturdays from 10am-2pm. Details and directions are available at www.cedarcreek.umn.edu/conservation/bison. You can also spot the bison on Cedar Creek’s trail cameras by classifying images at http://eyesonwild.com.