Boronia rivularis is a rare heathland shrub restricted the Sunshine Coast of Australia, an area undergoing rapid urbanisation. A development proposal is planning to translocate a population of this species from the southern end of its range. A previous study of genetic diversity in B. rivularis found a nearby population to be highly inbred and genetically depauperate compared with other populations. The study also found that, inbreeding was significantly positively correlated with population density. The population on the development site was mapped using a differential GPS and identified dense and sparser subpopulations and was used for initial translocation planning. We sampled the development site B rivularis within four sub populations using the same methods and markers as the previous genetic analysis. This study revealed genetic diversity was high in some subpopulations but progressively decreased as plant population density and fixation indices increased across the site in the direction of the neighbouring depauperate population. The large population size and the genetic structuring suggest the nearby population may have arisen from this one and highlights the benefits of retaining some of the existing population on the site. The results also indicate that any compensatory translocation program needs to mimic this the genetic substructuring. Largely due to its lower density, the subpopulation with the highest diversity and lowest inbreeding had not been previously valued as highly for translocation as the more conspicuous denser subpopulations. This study has highlighted that high population density does not necessarily indicate genetically fitter or more diverse subpopulations.
2005 International Conference of the Society for Ecological Restoration (SER): Ecological Restoration - A Global Challenge, Zaragosa, Spain 2005
Proceedings of the 2005 International Conference of the Society for Ecological Restoration / pp.140