Key to Bighorn Sheep Genetics May Lie in Historic Skulls
Contact: Teresa Zimmerman, (605) 433-5267
BADLANDS NATIONAL PARK, S.D. -- Researchers will be able to determine the genetic diversity of the historic and recent populations of bighorn sheep at Badlands National Park using DNA from blood and bone samples collected from 1992 through 1997. Researchers are also interested in comparing the genetics of these Rocky Mountain bighorn sheep found in South Dakota today to the extinct subspecies known as Audubon's bighorn. Researchers are asking for assistance in identifying potential sources of Audubon's bighorn skulls from South Dakota for DNA analysis.
"One of the goals of this genetics research project is to determine the effects of the 2004 translocation on the genetic diversity of the Badlands National Park bighorn sheep population and to determine if additional bighorn will be needed in future years to ensure sufficient genetic diversity for a healthy population," said Badlands wildlife biologistTeresa Zimmerman. In 2004, Badlands National Park and the South Dakota Department of Game, Fish and Parks translocated 23 bighorn sheep from Wheeler Peak, NM to Badlands National Park. The purpose of this translocation was to add genetic diversity to the existing population. Since their translocation, these introduced sheep have been the focus of a research project conducted through South Dakota State University in conjunction with Badlands National Park, the South Dakota Department of Game, Fish and Parks, and the U. S. Forest Service Rocky Mountain Research Station in Missoula, MT.
"In addition to studying the effects of the 2004 translocation on the population genetics, we want to find out more about the extinct subspecies known as Audubon’s bighorn," noted Zimmerman. "We are interested in examining the DNA from the Audubon’s bighorn for genes which play a role in disease and parasite resistance." The Audubon’s bighorn was historically found in eastern Montana and Wyoming and western South Dakota, North Dakota, and Nebraska. This subspecies became extinct in 1924 or 1925 when the last ram was harvested south of the White River in Washabaugh (Jackson) County, SD. Rocky Mountain bighorn, a relative of the Audubon’s bighorn, was introduced to the Black Hills in 1925 and to Badlands in 1964.
DNA from the extinct Audubon’s bighorn can only be obtained through sampling bone from known skull sources. To date, four samples have been collected from museum specimens at Badlands National Park and from the Illinois State Museum. Bill Fugate, manager of the Badlands Petrified Gardens also allowed researchers to sample an Audubon’s bighorn ram skull from his collection. Badlands National Park and the South Dakota Department of Game, Fish and Parks are working cooperatively to identify other potential sources of Audubon’s bighorn skulls from South Dakota for DNA analysis.
A small portion of bone is removed from inside the nasal cavity or inside the horn and sent to the Rocky Mountain Research Station for DNA extraction. Researchers are interested in skulls from animals which would have been alive prior to 1925. It is not illegal to possess a bighorn sheep skull if it was collected prior to 1972; therefore, anyone in possession of a skull like this is not in violation of any law. Anyone who owns a bighorn sheep skull which fits this description and is interested in allowing it to be sampled for genetics research may contact wildlife biologist Teresa Zimmerman with Badlands National Park at 605-433-5267 or Regional Wildlife Manager John Kanta with the South Dakota Department of Game, Fish and Parks at 605-394-1755 for additional information.