Several initiatives by the Australian Seafood CRC's Future Harvest theme involve some form of stocking or enhancement of fisheries. In WA, populations of Roe's Abalone are currently being restocked after a catastrophic mortality event, while stock enhancement of Greenlip Abalone is also occurring. The CRC is also supporting translocation of Southern Rocklobster and ranching of Sea Cucumbers. In all such cases there is a need to understand the population genetic dynamics of stocked populations and the extent of genetic interactions of stocked with wild populations (Flinders has been conducting his research for sea cucumbers using the traditional microsatellite marker approach in 2008/733). Important considerations are the genetic health of individuals used as breeders, genetic structuring of source populations, effective population size, effects on inbreeding or loss of genetic diversity, recruitment and geographic spread. Molecular markers can be used to investigate these effects and guide the stocking. Genomic technologies such as GBS are rapidly developing and becoming less expensive and more useful to apply than traditional genetic approaches. These new genomic techniques that directly genotype individuals using sequence information are extremely promising as they eliminate the need for species specific marker development and could provide an efficient and comprehensive means of studying genomes at an individual and population level. Importantly, contrary to traditional genetic methods such as microsatellite surveys, new genomic techniques such as GBS might provide ways of disclosing functional genetic variation (variation that is ecologically relevant and related to the fitness of the individual) or facilitating genomic selection. Once GBS data is mapped to areas of the genome with known function, marker assisted selection for traits of importance to aquaculture becomes possible.
Here we propose engaging a post-doc that will specialise in this area and assist projects with Flinders involvement on Roe's and Greenlip Abalone in Western Australia.
Final report
Several initiatives by the Australian Seafood CRC’s Future Harvest theme involve some form of stocking or enhancement of fisheries. In Western Australia, populations of Roe’s Abalone (Haliotis roei) are currently being restocked after the occurrence of a catastrophic mortality event, while stock enhancement of Greenlip Abalone (Haliotis laevigata) is also occurring. Translocation of undersized Southern Rocklobster from deep to shallow water locations and ranching of Sea Cucumbers is also occurring. In all such cases there is a need to understand the population genetic dynamics of stocked populations and the extent of genetic interactions of stocked with wild populations. Important considerations are the genetic health of individuals used as breeders, genetic structuring of source populations for restocking, effective population size (i.e. effective number of breeders), effects on inbreeding or loss of genetic diversity, recruitment and geographic spread. Molecular markers can be used to investigate these effects and guide the stocking. Genomic technologies such as Genotyping-By-Sequencing (GBS) are rapidly developing and becoming less expensive and more useful to apply than traditional genetic approaches. Therefore, this project employed a post-doctoral researcher with the following objectives:
- Develop new expertise and transfer genomic approaches, currently used for commercially important species of the Northern hemisphere, to benefit the fisheries or aquaculture of key commercial species in Australia
- Generate and use genomic data to analyse changes and patterns in functionally relevant genetic diversity (i.e. variation related to fitness) with restocking and ranching and advise on management strategies for the species concerned
- Develop expertise in genetic management associated with enhancement and related interventions
The overall benefit of this project was to create genetically healthy/sustainable restocked populations, improve returns from ranching while having minimal impact on natural populations and maintain healthy fisheries.
Genomic sequencing techniques were developed and found to be effective for both Roe’s Abalone and Greenlip Abalone. Three genetically distinct groups of Roe’s Abalone and five genetically distinct groups of Greenlip Abalone were defined and each of these groups showed high connectivity. This information will inform management approaches to the restocking of Roe’s abalone and contribute to the stock enhancement of Greenlip Abalone in Western Australia.
