Krogman Ranch Bison Excavation

A mass death site of fossil bison was excavated and studied by faculty and students at the University of South Dakota. The project began when a professor of education and a professor of law were seeking a scientific project in which to involve Native American students. Wayne Evans, the professor of education, had learned from relatives that bones were weathering out of a hillside on a ranch northeast of the town of White River in south-central South Dakota. Soon paleontologists Gary Johnson and Tim Heaton became involved, and two exploratory excavations were conducted. Staff from the W. H. Over Museum in Vermillion participated so that a museum exhibit would result from the work.

Tim Heaton and Wayne Evans were awarded a Bush mini-grant to fund the project in 1993, and the first major excavation was conducted in May of that year. This involved a group of twenty interdisciplinary faculty and students. In addition to the excavation, Wayne Evans obtained a teepee (one made for the film Dances with Wolves) and a sweat lodge where ceremonies were performed for the group in the evenings. Wayne also made tobacco offerings at the site of the deceased bison and led the group in singing and drum playing of Native American songs each morning. This continued on subsequent excavation trips.

The Krogman family, especially William and his son Roger, were very generous in their support of the project. They allowed the university access to the site at any time and provided water and other essentials as needed for the excavations. Bill, who died in November of 1995, was especially fond of the university group and enjoyed spending an hour or two each day helping dig the bones. Roger demonstrated his skill with a tractor when plaster blocks became too big to carry. Their help was greatly appreciated.

The bone deposit was located in a small hill at the edge of a badland bluff and was concentrated in a small area. Overburden had to be removed with a jackhammer to reach the center of the deposit. In some areas the bones were in such a dense tangle that they were hard to remove without damage. A grid system was established on the site, and each bone was mapped and numbered before removal. Over two thousand bones were removed. Several skulls and other delicate portions of the deposit were removed in plaster blocks for preparation in the laboratory.

The W. H. Over Museum in Vermillion provided space and supplies for the bone preparation and set up display cases to exhibit some of the best specimens. The preparation process was a live exhibit for several years where visitors could talk to the student preparators and see their work in action. Students unwrapped bones that were packaged in the field and cleaned and reassembled them. They were sorted into boxes and their locations and field identifications entered into a computer database. Some of the preparation was also conducted at Sinte Gleska University in Mission, South Dakota. The excavation and preparation was funded by two Bush grants and by a Howard Hughes Medical Institute grant that was awarded to USD.

The only report published to date is the abstract of a talk presented by Tim Heaton at the South Dakota Academy of Sciences meeting in Sioux Falls in 1994. A report was also published in the Friends of the Over Museum Newsletter. For further information contact Professor Heaton at