Population History and Non-invasive Monitoring : Use of low copy number DNA in Conservation Genetics

Abstract: Conservation genetics research is increasingly becoming an integrated part of the management of small and endangered populations. In this thesis I developed tools for genetic analysis of low copy number sources of DNA, such as old teeth from museum specimens as well as field-collected faeces and urine. The newly developed techniques were experimentally tested and were subsequently used in studies of small and vulnerable populations of three taxa.Swayne’s hartebeest, a critically endangered antelope of Ethiopia, has undergone a dramatic population decline during the 20th century. The decline was accompanied by loss of genetic variability, although only evident for the mtDNA genome. Two examined populations were significantly differentiated (p<0.001) and genetic variability was significantly lower (p<0.05) for the smaller population. The data demonstrated that a translocation of 120 animals in 1974 from the larger to the smaller population failed.The wolverine population in southern Norway is the smallest of three populations in Scandinavia. Individual identification of wolverines, based on genetic tagging of 147 faeces samples, provided an estimated population size of 92 ± 9 individuals. The data suggested that Swedish immigrants have contributed and still contribute to the gene pool in Southern Norway, counteracting genetic erosion and reducing the risk of inbreeding depression.The Scandinavian wolf was considered functionally extinct in the 1960s after a dramatic decline for more than a century. Genetic variability was lost during the 1800s and the first decades of the 1900s. Immigration from eastern populations appeared to be low during this period. After 1940, however, several immigrants were detected in the population, which could be related to population expansion events in Russian Karelia. A combined data set of historical and contemporary samples showed that two eastern immigrants founded the contemporary population in 1983. During the 1980s, severe inbreeding took place and genetic variability was again lost. However, with the arrival of a single male immigrant in 1991, there is evidence of increased heterozygosity, a rapid spread of new alleles, and exponential population growth, implying that rare immigration can lead to the rescue and recovery of isolated and endangered populations.