Reducing the bycatch pf juvenille bream, luderick and mullet in the NSW ocean haul fishery. To ensure long-term sustainability of the targeted species, it is imperative that the ocean haul fishery implements conservation-orientated practices. Failure to reduce the mortality of bycaught bream, luderick and mullet in the ocean haul fishery is likely to impact on the quality of both commercial and recreational fishing for these important species. The aims of the project are to (i) determine selecti ....Reducing the bycatch pf juvenille bream, luderick and mullet in the NSW ocean haul fishery. To ensure long-term sustainability of the targeted species, it is imperative that the ocean haul fishery implements conservation-orientated practices. Failure to reduce the mortality of bycaught bream, luderick and mullet in the ocean haul fishery is likely to impact on the quality of both commercial and recreational fishing for these important species. The aims of the project are to (i) determine selectivity of the existing nets used and (ii) to develop and assess modifications to gears that reduce bycatch. More specifically the utility of simple changes to existing mesh sizes and shapes to improve selectivity and bycatch reduction devices will be investigated. The expected outcomes of this project will be the conservation of hundreds of thousands of juvenile fish ensuring a better fishery, whilst also securing the economic and social structure of coastal communities that support this fishery.Read moreRead less
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
Stocking of fish and prawns at ecologically determined densities into Australian estuaries. Increasing numbers of people like to go fishing, and to catch a fish, which translates into tourism income and aquaculture business. Restocking is a fisheries management option when the natural supply or survival of larvae is limited. This study will determine for the first time the ecologically appropriate abundance of small mulloway and prawns that an estuary can sustain. We will assess the extra eff ....Stocking of fish and prawns at ecologically determined densities into Australian estuaries. Increasing numbers of people like to go fishing, and to catch a fish, which translates into tourism income and aquaculture business. Restocking is a fisheries management option when the natural supply or survival of larvae is limited. This study will determine for the first time the ecologically appropriate abundance of small mulloway and prawns that an estuary can sustain. We will assess the extra effort needed to release larvae into particular key habitats, and develop new technologies to identify our larvae from the wild. Our findings will be relevant to restocking of Australia's inland rivers, which at present has little ecological basis.Read moreRead less
Phylogeography, Conservation Genetics and Stocking Management of Perches and Basses. This project will use DNA data to address fundamental questions about the origin and maintenance of biodiversity in a popular and widely distributed fish group. From a conservation perspective, the project will produce a benchmark about management of fish resources. We will investigate questions related to important conservation issues (including the recovery plan of a nationally threatened species) and the mana ....Phylogeography, Conservation Genetics and Stocking Management of Perches and Basses. This project will use DNA data to address fundamental questions about the origin and maintenance of biodiversity in a popular and widely distributed fish group. From a conservation perspective, the project will produce a benchmark about management of fish resources. We will investigate questions related to important conservation issues (including the recovery plan of a nationally threatened species) and the management of stocking activities in recreational fisheries of coastal and inland waters. The latter is particularly relevant to rural communities since they provide both social and economic benefits to rural people.Read moreRead less
Linking freshwater flows, salt wedge dynamics and fisheries productivity in estuaries. Freshwater is a critical resource in Australia, but there is a perception that freshwater running to the sea is wasted. Australia's estuaries are of great importance - economically, socially and environmentally. Estuaries provide habitat for unique and endangered animals and plants, support valuable fisheries, and have enormous recreational value, particularly in regional communities. Our lack of understanding ....Linking freshwater flows, salt wedge dynamics and fisheries productivity in estuaries. Freshwater is a critical resource in Australia, but there is a perception that freshwater running to the sea is wasted. Australia's estuaries are of great importance - economically, socially and environmentally. Estuaries provide habitat for unique and endangered animals and plants, support valuable fisheries, and have enormous recreational value, particularly in regional communities. Our lack of understanding about the effects of freshwater flows on estuarine productivity impedes decision making on the allocation of water to sustain healthy estuaries. The health of Australia's estuaries and sustainability of their resources, particularly fisheries, depend on understanding their freshwater requirements and securing environmental flows.Read moreRead less
Enhancement of fish stock by habitat manipulation in artificial coastal waterways. Human settlement significantly changes the spatial characteristics of natural coastal waterways. The value of artificial waterways, such as canals, as a habitat for fish is poorly known. We will evaluate the significance of artificial canals as a fish habitat, and test the effect of habitat modification by artificial reef installation on fish distribution and abundance. We will investigate whether artificial reefs ....Enhancement of fish stock by habitat manipulation in artificial coastal waterways. Human settlement significantly changes the spatial characteristics of natural coastal waterways. The value of artificial waterways, such as canals, as a habitat for fish is poorly known. We will evaluate the significance of artificial canals as a fish habitat, and test the effect of habitat modification by artificial reef installation on fish distribution and abundance. We will investigate whether artificial reefs enhance fish production in canals, rather than simply acting as fish aggregation devices. This research will address an important question in fisheries ecology and help formulate management guidelines for artificial waterways.Read moreRead less
Native fish stocking of rivers: discriminating between hatchery-reared and wild fish. Stocking of fish is widely used in attempts to restore native fish populations. Little is known of the fate of stocked fish or the effects of stocking on resident populations. We will develop and evaluate protocols for chemical marking of otoliths of hatchery-reared fish so that their source can be determined. Experimental stocking of hatchery-reared fish will be undertaken and population structure and sourc ....Native fish stocking of rivers: discriminating between hatchery-reared and wild fish. Stocking of fish is widely used in attempts to restore native fish populations. Little is known of the fate of stocked fish or the effects of stocking on resident populations. We will develop and evaluate protocols for chemical marking of otoliths of hatchery-reared fish so that their source can be determined. Experimental stocking of hatchery-reared fish will be undertaken and population structure and source of stocked versus wild fish determined in stocked and unstocked rivers. Natural chemical signatures will also help determine important recruitment areas. The outcomes will allow fisheries managers to make informed decisions regarding stocking strategies.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE100100059
Funder
Australian Research Council
Funding Amount
$100,000.00
Summary
Dual frequency identification SONAR (DIDSON) facility for sampling benthic and pelagic fish populations. Many Australians enjoy marine and freshwater resources, and we are exploiting fisheries and waterways in particular at an increasing rate. Effective management of fisheries requires understanding the abundance and behavior of fish. This facility will provide novel acoustic video technology for researchers to count fishes and sharks near weirs, under wharves or logs, and within seagrass beds. ....Dual frequency identification SONAR (DIDSON) facility for sampling benthic and pelagic fish populations. Many Australians enjoy marine and freshwater resources, and we are exploiting fisheries and waterways in particular at an increasing rate. Effective management of fisheries requires understanding the abundance and behavior of fish. This facility will provide novel acoustic video technology for researchers to count fishes and sharks near weirs, under wharves or logs, and within seagrass beds. The dual frequency identification sonar (DIDSON) will also allow accurate and standardised study of fish movements in response to floods, algal blooms or re-stocking events without disturbing the fish or their habitats. This will enhance our understanding of the top-down control by fish of aquatic ecosystems that are directly adjacent to human activity.Read moreRead less
Trophic cascades in Australian seagrasses: linking nutrients to survival and growth of commercially-important fishes. Despite its high conservation status and importance to commercial and recreational fisheries, seagrass is still declining in Australian waters. By investigating a trophic cascade that links nutrient pollution to the growth and survivorship of seagrass and commercially-important juvenile fishes, our study fills knowledge gaps crucial for improved future management of seagrass hab ....Trophic cascades in Australian seagrasses: linking nutrients to survival and growth of commercially-important fishes. Despite its high conservation status and importance to commercial and recreational fisheries, seagrass is still declining in Australian waters. By investigating a trophic cascade that links nutrient pollution to the growth and survivorship of seagrass and commercially-important juvenile fishes, our study fills knowledge gaps crucial for improved future management of seagrass habitats. The primary outcome of this study will be a model that can predict how changes in nutrient pollution will influence population dynamics of commercially-important fish species supported by seagrass. This information has, therefore, direct relevance to managers of estuarine and coastal environments at all levels of government - local, state and federal.Read moreRead less
Feeding and breeding: Rainfall effects on connectivity and fidelity of iconic coastal fishes. Large predatory fish are of great significance to recreational anglers, not only for their trophy status but also for their disproportional fecundity and contribution to future fishing. Remarkably, the distribution and movements of large estuarine fish in estuaries and the coastal ocean are unknown, despite their importance to the national economy. We will determine the role of freshwater discharge an ....Feeding and breeding: Rainfall effects on connectivity and fidelity of iconic coastal fishes. Large predatory fish are of great significance to recreational anglers, not only for their trophy status but also for their disproportional fecundity and contribution to future fishing. Remarkably, the distribution and movements of large estuarine fish in estuaries and the coastal ocean are unknown, despite their importance to the national economy. We will determine the role of freshwater discharge and oceanography on the coastal and estuarine habitat requirements, movements and home ranges of mulloway, flathead and bream from the scale of hours to years, and extend these findings to evaluate population sub-structuring and connectivity in the context of a changing climate.Read moreRead less