Bison Grazing for Grassland Bird Habitat

The goal of the bison grazing partnership is to utilize bison as another tool to manage prairie and grassland habitat for the benefit of breeding birds and other wildlife. The District is committed to advancing its conservation goals through data-driven, conservation-oriented farm management using practices that protect soil and water resources, conserve wildlife habitat, and regenerate ecological function. We continue to seek innovative ways to accomplish these goals through new partnerships. 

Bison are a native species that historically played a keystone role in the ecology of prairies and grasslands, and they are an excellent management tool for prairie ecosystems. They help keep the balance of habitat structure and species composition of the prairie. Their grazing and wallowing behavior creates a mosaic of microhabitats for grassland birds, pollinators, and other wildlife. Bison are also more selective in their grazing habits, which promotes a more diverse plant community.  It is important to the prairie habitat to have grazers part of the land management.  The bison are doing the work of managing the prairie, and in a far more natural and beneficial way for wildlife. 

In 2021, the Conservation District entered into a 15-year lease agreement on 30 acres of pastureland at Pleasant Valley Conservation Area in Woodstock to Ruhter Bison LLC  to raise young bison (age 1-3 year-old animals)  The Conservation District is using a low stocking rate and rotating the herd to manage the habitat. Ruhter Bison is dedicated to wildlife conservation and protecting natural resources.

For the health and safety of the animals, this section of Pleasant Valley is closed to the public. Future plans include offering public education programs and tours a few times each year.


The Benefits of Bison Grazing
Bison are a keystone species of the prairie ecosystem and grazers play an important role in prairie restoration. Bison grazing is a natural management tool for enhancing the biological diversity of our local prairie, while benefitting the habitat of grassland breeding bird species and other wildlife.

Grazing creates a vegetation structure that is attractive to many grassland birds. At one time, grassland bird species evolved alongside these large grazers. Declining grassland bird species such as grasshopper sparrows, bobolinks, upland sandpipers, and savannah sparrows prefer the shorter, patchier structures of grazed pastures vs. the taller, more uniform structure of prairie restorations. District breeding bird data has shown higher densities of some of these species in cattle grazed pastures than in adjoining prairie restorations.

Bison are primarily graminoid feeders. Because they prefer grasses and tend to leave forbs ungrazed they can increase light availability to ungrazed forbs providing benefits to some forb species. Removal of the grass canopy also results in warmer soil temperatures and increased soil moisture, which may stimulate earlier growth of ungrazed forbs in the spring.

Bison grazing also alters nutrient cycling processes and nutrient availability. Insects and bacteria decompose their feces, helping to recycle nutrients back into the soil. Their waste also spreads seeds. Their hooves plant seeds in the soil while leaving divots that hold moisture. Bison also help disperse seeds that get caught in their thick fur and are distributed throughout the prairie.