The Importance of Genetic Considerations for Planning Translocations of the Rare Coastal Heath Species Boronia rivularis (Rutaceae) in Queensland

Abstract

The Sunshine Coast of Queensland, Australia, is facing increasing pressure from rapid urban expansion. Because of the area’s high biodiversity, developers are facing pressure to translocate rare, endangered, and vulnerable plants to more protected areas. Translocation of turves, comprising sections of soil and intact aboveground vegetation, has been used as a strategy for reintroducing understory species where establishment from seed is difficult. Moving populations spatially can change levels and direction of gene flow. In what appears to be one of the largest reported translocations of a rare species, this study uses allozymes, which are variant forms of enzymes, to investigate the genetics of a population of the rare heath species Boronia rivularis, which is to be translocated to compensate for an urban development. The population on the development site was found to be significant due to its large size and high genetic diversity and distinctiveness. Diversity and inbreeding levels were not evenly distributed across the development site; inbreeding was highest where density was highest. It was found that retention of a significant portion of the population on the development site reduced the potential loss of connectivity. However, we found that ecological assessments based on density could have led to the loss of the most genetically diverse and least inbred parts of the population.