A genetic and experimental assessment of the frequency and importance of hybridisation of Black and Yellow Fin Bream. Bream (Acanthopagrus spp.) species underpin several valuable and heavily exploited fisheries in eastern Australia, but the two principal species, yellowfin (A. australis) and black (A, butcheri), interbreed significantly. This hybridisation is poorly documented and, with increasing harvests, could lead to long-term economic impacts and severe repercussions on biodiversity. It cou ....A genetic and experimental assessment of the frequency and importance of hybridisation of Black and Yellow Fin Bream. Bream (Acanthopagrus spp.) species underpin several valuable and heavily exploited fisheries in eastern Australia, but the two principal species, yellowfin (A. australis) and black (A, butcheri), interbreed significantly. This hybridisation is poorly documented and, with increasing harvests, could lead to long-term economic impacts and severe repercussions on biodiversity. It could, for example, increase the risk of localised extinctions and impact on genetic diversity of both species. We will use an innovative combination of molecular genetics and breeding experiments to: (i) determine frequency and direction of hybridisation; (ii) infer strength of genetic connections among estuaries; and, (iii) explore implications for sustainable fisheries management.Read moreRead less
Variation in larval gene expression in a marine invertebrate: implications for population divergence via differential settlement response. Evolutionary and ecological functional genomics is an emerging field that integrates gene profiling technologies with experimental and field approaches of ecology and evolution. I take this approach to address a key problem in marine invertebrate biology: how do larvae respond to their environment and how does variation in this response influence the distribu ....Variation in larval gene expression in a marine invertebrate: implications for population divergence via differential settlement response. Evolutionary and ecological functional genomics is an emerging field that integrates gene profiling technologies with experimental and field approaches of ecology and evolution. I take this approach to address a key problem in marine invertebrate biology: how do larvae respond to their environment and how does variation in this response influence the distribution and evolution of a species? I will use a marine gastropod (abalone) model, for which there exists substantial development and population genetic data, and established aquaculture methodologies. Outcomes of this study will enhance knowledge of the stock structure of this and other commercial fisheries, as well as aquaculture efficiency.Read moreRead less
Population structure in the giant Australian cuttlefish - implications for management of a unique eco-tourism and fishery resource in regional Australia. A management strategy for the giant Australian cuttlefish in regional South Australia is required urgently because of potential conflict between ecotourism and fishery sectors. At present, development of a management strategy is stymied by lack of information on stock structure and movements. Analyses of variation in gene frequencies, morphom ....Population structure in the giant Australian cuttlefish - implications for management of a unique eco-tourism and fishery resource in regional Australia. A management strategy for the giant Australian cuttlefish in regional South Australia is required urgently because of potential conflict between ecotourism and fishery sectors. At present, development of a management strategy is stymied by lack of information on stock structure and movements. Analyses of variation in gene frequencies, morphometric and chemical trace element profiles in calcified structures among locations and years will enable the geographic extent of populations or stocks to be determined, including whether natal homing occurs. Such information is critical to sustainable management of the species and design of a marine protected area in the upper Spencer Gulf.Read moreRead less
Intersexual arms races - are individuals within marine meta-populations less able to interbreed than assumed? A meta-population structure is thought to describe the inter-connected nature of many populations of marine animals with dispersive larvae. However, new theory predicts some of these populations might be not very inter-connected at all, despite larval migration. In some circumstances, independent, co-evolutionary arms races between sexes might develop within local populations, resulting ....Intersexual arms races - are individuals within marine meta-populations less able to interbreed than assumed? A meta-population structure is thought to describe the inter-connected nature of many populations of marine animals with dispersive larvae. However, new theory predicts some of these populations might be not very inter-connected at all, despite larval migration. In some circumstances, independent, co-evolutionary arms races between sexes might develop within local populations, resulting in individuals becoming increasingly less able to interbreed freely. I will directly test for this, measuring how successfully broadcast spawners can cross-fertilise across populations. This will reveal the genetic structure of these populations and if these animals really do live in a meta-population.Read moreRead less
Larval Dispersal And The Design Of Marine Reserve Networks: Benefits Within And Beyond Boundaries. Most marine organisms produce tiny offspring that are dispersed unknown distances by oceanic currents. Our present strategies to manage marine resources lack this vital piece of information. This study will apply two revolutionary techniques that finally enable us to determine how far marine larvae travel. Using the team that developed these techniques, field studies will for the first time measure ....Larval Dispersal And The Design Of Marine Reserve Networks: Benefits Within And Beyond Boundaries. Most marine organisms produce tiny offspring that are dispersed unknown distances by oceanic currents. Our present strategies to manage marine resources lack this vital piece of information. This study will apply two revolutionary techniques that finally enable us to determine how far marine larvae travel. Using the team that developed these techniques, field studies will for the first time measure both retention of fish larvae within marine protected areas and dispersal of larvae to adjacent fished areas on coral reefs. This information can be directly applied to optimize the size of reserves and their spacing in marine protected area networks.Read moreRead less