This thesis examines the genetic and ecological consequences of the introduction of exotic Japanese sika deer (<I>Cervus nippon nippon</I> Temminck. 1838) to the range of congeneric red deer (<I>Cervus elaphus scoticus</I> L. 1758) in Scotland. Sika were introduced as result of escapes and deliberate releases of park deer around the turn of the century and have since established feral populations in several locations. Most of these populations are achieving high reproductive rates, are currently expanding their range and are hybridising with red deer. These circumstances are of practical concern as red deer have considerable economic importance in Scotland, both for the positive values of stag stalking and leisure use of the hills and through the negative effect of damage to crops and forestry. The situation is also of biological importance as it provides a rare opportunity to assess the genetic structure of a hybrid population after an introduction and to examine the functional significance of hybridisation affecting quantitative traits. Sampling transects were established across two sympatric sika-red population ranges, in Argyll and Invernesshire. Genotypes of 235 deer from nine forests in Argyll and 136 deer from 7 forests in the Great Glen, Invernesshire, were scored at 2 isozyme, 2 microsatellite and 3 mitochondrial DNA (mtDNA) marker loci. The species-specific mtDNA markers were generated within this study. Clines in sika allele frequency were found across both transects, with sika frequency reaching 0.8 in Argyll and fixation (1.0) in Invernesshire. Sika are assumed to have at least one and probably several selectively advantaged genes to account for this consistent and rapid increase in frequency. There were significant heterozygote deficits and linkage disequilibria in the centre of the clines, even though samples in the Great Glen were small. MtDNA clines were steeper than nuclear clines, indicating the role of sika or hybrid stags in propagating the advance, but patterns of cytonuclear disequilibrium were not informative about mating pattern, due to the possibility of hybrid immigration and the influence of heterozygote deficit reducing sample sizes. There was no evidence of directionality in the F1 cross, though assortative mating in the backcross could contribute to the linkage disequilibrium observed, as could selection against hybrids.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:640129 |
| Date | January 1994 |
| Creators | Abernethy, Katharine Anne |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/11564 |
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