Modern science and wildlife conservation have combined to return American bison with complete heirloom genetics – from in and around Yellowstone National Park – to their historic range on the Northern Colorado prairie. Modern fertility science, supplied by reproduction experts at Colorado State University's Animal Reproduction and Biotechnology Laboratory, helped to enable the homecoming, in part by coupling Yellowstone bison in the laboratory and cleansing reproductive cells and embryos of the infectious disease, brucellosis. The city of Fort Collins and Larimer County are providing habitat that is the essential first step for any wildlife conservation effort. The local government agencies have used land purchases and conservation easements to preserve nearly a quarter-million acres of land stretching from Northern Colorado’s Rocky Mountain foothills to the Plains.