9622126 Derr Worldwide, many species of large vertebrates have, or soon will, encounter population challenges similar to what occurred in the last century with bison. Many of these species, like bison, are polygynous and now are limited to highly fragmented and managed ecosystems. This research will investigate genetic diversity in North American bison populations before and after the human induced population bottleneck of the last century. In the last 100 years, population sizes have recovered. The primary founders for this restoration effort have come from only five herds, four from the northern herd, and one from the southern herd. This research is designed to test the conservation question that relatively low levels of genetic polymorphisms in extant populations are a direct result of the 19th Century bottleneck and that conservation efforts should be directed at maximizing the remaining genetic variation among herds. To test this hypothesis, polymerase chain reaction and nucleotide sequencing will be used to examine genetic diversity in both mitochondrial and nuclear genomes of extant and historical (pre-bottleneck) populations. Historical population data will be derived from the extensive fossil materials available. Because conservation and restoration efforts have proved so successful with bison, they provide an ideal model system to develop management plans for the genetic effects of population bottlenecks and habitat fragmentation for other megavertebrate species. This study will have direct bearing on the ability of populations to regain genetic diversity, and on issues regarding minimum viable population size of large vertebrates.
