Spatio-temporal genetic variation in wild animal and plant populations in Sweden and its relevance for conservation genetic monitoring

Abstract: Human impact on the world’s ecosystems is massive, resulting in habitat destruction and fragmentation that strongly affects the future survival of non-human life forms. Typically, biodiversity loss at the genetic level is much less recognized as compared to the levels of species and ecosystems, and information on reduction of natural gene pools is frequently missing unless coupled with loss of an entire species. To detect reductions or changes in genetic composition, genetic variation must be studied over time (genetic monitoring). Presently, monitoring is to a larger scale implemented at the ecosystem and species levels to identify biodiversity loss, whereas monitoring programs at the gene level are still missing for most species.This thesis focuses on “conservation genetic monitoring”, which I and my co-authors have defined to include identifying and safeguarding gene level biodiversity for the implementation of the Convention of Biological Diversity (CBD). Amount of genetic variation, genetic composition, and spatial genetic structure must be systematically studied over time to detect potential changes of these parameters that can reflect in loss of gene level biodiversity.Paper I of this thesis suggests categories of species for which monitoring genetic diversity appears particularly urgent on the basis of e.g. level of exploitation and threat status. We stress that a basic description of a species´ spatial distribution of genetic variation at some point in time represents a primary prerequisite for future monitoring. Therefore, literature searches were conducted to collect information on the current knowledge regarding spatio-temporal genetic variation in wild animal and plant populations in Sweden. Basic starting points for “conservation genetic monitoring” of Swedish species is fairly limited. A total of 775 scientific studies including genetic information for a total of 374 species were found, but most of them (277) were directed towards only a few species of bony fishes and forest trees. Only four percent of the studies also included temporally spaced samples. For several species for which conservation genetic monitoring is considered particularly urgent genetic data is missing. One such species is the moose (Alces alces), the demography of which is almost completely controlled by man. Various moose hunting strategies are expected to directly affect the genetically effective population size and generation interval, factors that govern the rate of loss of genetic variation. These potential effects are insufficiently recognized among managers, and genetic data is largely missing for this ecologically and socio-economically important mammal. Paper II focuses on the generation of basic information on the spatial genetic structure of the Swedish moose population using six microsatellite loci. The results indicate that the moose in Sweden does not constitute a single panmictic unit, and there are indications of a local bottleneck in one area. For an evolutionary sustainable management of the moose, it is important that management and genetic groupings coincide.