Effects of translocation on population genetics and demographics of a northern bobwhite (Colinus virgnianus) population among a fragmented landscape in southwestern Georgia
Terhune, Theron Menees
MetadataShow full item record
Large scale, contemporary studies of genetic and demographics of a non-migratory, avian species in fragmented landscapes are scarce. Changing land-use and increased urbanization have drastically affected wildlife ecosystems and their inhabitants via fragmentation. The paucity of genetic and demographic information for these species generates a gap in the study of population dynamics within these ecosystems, both among avian species, specifically, and all organisms, generally. Thus, knowledge of the effects changing land-use has on population persistence is precarious at best. The philopatric, non-migratory, and sedentary nature of many of these species potentially limits genetic exchange, contributing to variable demographics, both temporally and spatially, and purported population declines among fragmented, isolated landscapes. It has been proposed that translocation of individuals between populations may mitigate many of the negative effects of habitat fragmentation and isolation. To date, numerous translocations of multiple species have occurred. However, few have investigated the associated demographic and genetic ramifications. Translocation may serve as an artificial means of dispersal and subsequently introduce novel genes to isolated populations, potentially influencing demographic parameters (e.g., increasing fecundity). Furthermore, it is possible that translocation may operate as a conservation tool for restoring populations of declining and threatened species and, ostensibly, may be of increasing value for biodiversity conservation. However, prior to instituting this technique as a widespread management tool, its efficacy warrants investigation using a native, ubiquitous species not considered Endangered or Threatened. This dissertation addresses questions germane to translocation by integrating data from molecular lab techniques (microsatellite analysis) with field data collected through radio-location and spatial data present in a geographical information system. I selected the Northern Bobwhite (Colinus virginianus), a non-migratory, gallinaceous species of low-mobility, as my model species. Northern Bobwhites are particularly sensitive to habitat fragmentation, have suffered keen population declines during the past several decades, are a socio-economically important game bird, and exhibit a flexible mating regime that have demonstrated a strong propensity to respond rapidly to favorable habitat conditions. Therefore, using Northern Bobwhites logically allows for application of results to numerous species necessitating early-succession ecosystems and exhibit similar life-history characteristics. My research objectives were to determine: the efficacy of translocation to an isolated population of northern bobwhite, temporal and spatial limitations associated with translocation, and demographic disparities between translocated and resident bobwhites. I also examined genetic effects of translocation in northern bobwhites by: determining genotypic differences among resident and translocated bobwhites prior to initial release; tracking novel allele movement and allele frequency change through space and time; and investigating the magnitude of introgression. This research begins to fill significant gaps with regard to scientific knowledge of translocation effects on fragmented ecological systems, meta-population dynamics, and population genetics.