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Abstract: Lutjanus carponotatus ranges from the Indian Ocean to northern Australia and Papua New Guinea and is an important species for both commercial and recreational fisheries. Due to its life history characteristics and fishing pressures, L. carponotatus is vulnerable to overfishing and suitable management is essential. This phylogenetic and population genetic study assessed the population genetic structure of L. carponotatus at seven locations in three bioregions in Western Australia (WA) using the mitochondrial DNA control region. Analysis of molecular variance (AMOVA) indicated no genetic differentiation among locations within (ø CT =0.051) and among bioregions (ø SC =−0.026). Phylogenetic analyses indicated no geographic partitioning within WA, though two distinct lineages were found. Within these two lineages there was no significant spatial partitioning, suggesting a panmictic population that can, under current conditions, be managed as a single stock. WA and Great Barrier Reef (GBR) population genetic data were then combined to determine the broad-scale connectivity between the east and west coast of Australia. L. carponotatus from the GBR did differ significantly (F ST =0.64, p = <0.001) from the WA population, indicating the two populations do not exchange any migrants and should be managed as discrete stocks. As an indicator of population resilience, genetic variability was compared among WA and GBR populations of L. carponotatus and we show that the WA population has almost three times the genetic variability of the GBR population, suggesting that it will be better able to adapt to environmental change expected during the 21st century. [Copyright &y& Elsevier]

Abstract: The density and biomass of two coral reef fish species targeted by line fishers, Plectropomus maculatus and Lutjanus carponotatus, have increased within no-take marine protected areas on inshore reefs of the Great Barrier Reef (GBR). This phylogenetic and population genetic study, using mitochondrial DNA (mt DNA) from the control region, is a broad scale analysis of the genetic connectivity of P. maculatus (n =164) and L. carponotatus (n =188) within and between inshore islands of the GBR (latitudinal gradient 800km) that contain the aforementioned no-take areas. Analysis of molecular variance (AMOVA) indicated high levels of gene exchange between locations within (P. maculatus øCT =−0.011; L. carponotatus øCT =0.004) and between each island group (P. maculatus øSC =0.003; L. carponotatus øSC =0.003). Phylogenetic analysis showed no geographic partitioning but identified two distinct lineages for both species that were distributed throughout the sampled range, suggesting that both species are admixtures of differentiated lineages rather than stable populations. This study shows that populations of both species within the sampling range are panmictic and under current conditions, they may be managed as a single stock across the entire GBR. Thus, the study suggests that the island groups and the no-take marine protected areas within them are connected by larval transport to each other and to fished areas. This study cannot confirm if this connectivity is historical (evolutionary) or contemporary (ecological). [Copyright &y& Elsevier]