The role of genetic diversity in the conservation of rapidly declining seagrass meadows

All available evidence suggests that having higher genetic diversity within a species enhances population performance. Investigating these effects is integral to understanding mechanisms behind differences in productivity,... [ view full abstract ]

All available evidence suggests that having higher genetic diversity within a species enhances population performance. Investigating these effects is integral to understanding mechanisms behind differences in productivity, resilience and rehabilitation success. For predominantly clonal organisms, this relationship is particularly important, as the absence of sexual reproduction may result in very low genetic diversity. Here I focus on the diversity and performance of a predominantly clonal, threatened seagrass species, Posidonia australis, which is considered endangered along much of its distribution on the east coast of Australia. Using aerial imagery I confirmed that populations of P. australis along the southeast coast are currently under significant threat from anthropogenic activities and are prime candidates for restoration. I quantified genetic diversity and phenotypic variation within and among 12 meadows across their full distribution on the east coast. Using a series of field experiments, I show that increased genetic diversity of P. australis meadows can increase the likelihood of resilience to short-term stress and significantly improve restoration efforts.