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
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
A novel approach to tracking estuarine food chains: combined use of fatty acid and stable isotope biomarkers. Fatty acid biomarkers provide promising novel tracers for studying estuarine food chains. Stable isotopes, commonly employed in food chain studies, lack specificity to allow easy determination of feeding relationships. Different primary producers are characterised by unique fatty acid sequences. This study will thoroughly evaluate the applicability of fatty acid biomarkers in tracking ....A novel approach to tracking estuarine food chains: combined use of fatty acid and stable isotope biomarkers. Fatty acid biomarkers provide promising novel tracers for studying estuarine food chains. Stable isotopes, commonly employed in food chain studies, lack specificity to allow easy determination of feeding relationships. Different primary producers are characterised by unique fatty acid sequences. This study will thoroughly evaluate the applicability of fatty acid biomarkers in tracking both natural and human-impacted estuarine food chains. By developing a new approach of combining the advantages of fatty acid bioamrkers and stable isotopes in studying estuarine trophodynamics, this study will provide essential information for the management of estuarine biotic resources.Read moreRead less
Heterogeneity and ecosystem function: The role of microphytobenthos and macrofauna in inducing spatial variability in biogeochemical processes and fluxes. Human disturbances such as eutrophication (nutrient enrichment) increasingly threaten the sustainable use of Australia's coastal seas. Management of threats such as eutrophication are usually based on observations at large spatial scales, but ecological processes underpinning nutrient dynamics occur at much smaller scales. This multi-disciplin ....Heterogeneity and ecosystem function: The role of microphytobenthos and macrofauna in inducing spatial variability in biogeochemical processes and fluxes. Human disturbances such as eutrophication (nutrient enrichment) increasingly threaten the sustainable use of Australia's coastal seas. Management of threats such as eutrophication are usually based on observations at large spatial scales, but ecological processes underpinning nutrient dynamics occur at much smaller scales. This multi-disciplinary study will examine the relationship between processes mediated by small organisms (microscopic algae and burrowing animals), and large-scale nutrient dynamics pattern on sheltered coasts. Modern technologies will be used for monitoring the micro-scale processes, allowing models to be constructed to benefit both scientists and policy-makers alike.Read moreRead less
The mechanisms of settlement success in coral reef fishes. Most marine fishes, including commercial species, produce larvae that disperse in the open ocean. The short period during which these larval fishes leave the open water and take up residence on adult benthic habitat (settlement) is critical in determining the success of the population, but is poorly understood. Settling larvae differ in their physical attributes, including body size and physiological condition, both of which affect the ....The mechanisms of settlement success in coral reef fishes. Most marine fishes, including commercial species, produce larvae that disperse in the open ocean. The short period during which these larval fishes leave the open water and take up residence on adult benthic habitat (settlement) is critical in determining the success of the population, but is poorly understood. Settling larvae differ in their physical attributes, including body size and physiological condition, both of which affect their vulnerability to predators and their ability to compete for food and grow. By looking closely at this short life history stage, we hope to better understand how the supply of offshore larvae controls the production of marine fishes, including commercial fisheries.Read moreRead less
Conservation ecology of the black cod (Epinephelus daemelii). Black cod is a large, reef fish species that was once common and commercially important in NSW. Today, Black Cod is listed as vulnerable, and we know little more of their biology than when they were first protected in 1983. This project will significantly increase the effectiveness of Black cod management by determining their distribution, abundance, stock structure, fecundity, spawning behaviour and recruitment. This will allow imple ....Conservation ecology of the black cod (Epinephelus daemelii). Black cod is a large, reef fish species that was once common and commercially important in NSW. Today, Black Cod is listed as vulnerable, and we know little more of their biology than when they were first protected in 1983. This project will significantly increase the effectiveness of Black cod management by determining their distribution, abundance, stock structure, fecundity, spawning behaviour and recruitment. This will allow implementation of an effective recovery plan and a review of the status of Black Cod internationally and by the Federal Government. Collaboration with NSW Fisheries' Grey Nurse Shark program will allow assessment of the importance of Grey Nurse critical habitat areas in maintaining Black Cod populations.Read moreRead less
How connected are marine populations? Comparing life histories of endemic and non-endemic reef fishes to investigate the mechanisms behind self-recruitment. Recruitment of pelagic larvae plays a fundamental role in benthic marine populations, yet the sources and destinations of recruits are unknown for nearly all marine species. Because endemic species rely on retention of locally spawned larvae, they provide a novel opportunity for investigating the mechanisms allowing self-recruitment. I prop ....How connected are marine populations? Comparing life histories of endemic and non-endemic reef fishes to investigate the mechanisms behind self-recruitment. Recruitment of pelagic larvae plays a fundamental role in benthic marine populations, yet the sources and destinations of recruits are unknown for nearly all marine species. Because endemic species rely on retention of locally spawned larvae, they provide a novel opportunity for investigating the mechanisms allowing self-recruitment. I propose to compare the life histories and microchemical signatures in larval otoliths of endemic and closely related non-endemic reef fishes to determine the mechanisms and prevalence of self-recruitment. The results will broaden our understanding of how marine populations are replenished, information critically needed for marine conservation and resource management.Read moreRead less
Immediate and delayed changes to survival, physiology, reproduction and movement of chondrichthyans following capture stress. Many sharks and rays are negatively affected by the impact of fisheries capture, with unknown consequences. The project will measure changes to survival, physiology, reproduction and behaviour following capture to better understand and manage the impact of fisheries on these animals. This information is vital for their effective conservation.
Do larval fish leave the reef to avoid parasites? Although fundamental to understanding the community structure of reef fishes, why fish larvae migrate to the open ocean remains controversial. Traditional explanations are that it results in dispersal, avoidance of predators, and increased food. Recent work on the Great Barrier Reef, however, suggests avoiding reef-based micropredatory parasites may be more important. To determine if this so, we will investigate the effect of parasites on larval ....Do larval fish leave the reef to avoid parasites? Although fundamental to understanding the community structure of reef fishes, why fish larvae migrate to the open ocean remains controversial. Traditional explanations are that it results in dispersal, avoidance of predators, and increased food. Recent work on the Great Barrier Reef, however, suggests avoiding reef-based micropredatory parasites may be more important. To determine if this so, we will investigate the effect of parasites on larval fish condition, performance, and susceptibility to micropredators; whether larval fish are vulnerable to reef-based micropredators; the effects of micropredators on fish settlement patterns; and whether larval fish that don't migrate have adaptations to avoid micropredators.Read moreRead less
Living on the edge: settlement dynamics of reef fishes across their ranges. Settlement and early establishment (recruitment) are major determinants of population viability of marine organisms, and can vary greatly among oceans and latitudes. We will compare the recruitment dynamics of populations of reef fishes across their range, including at range boundaries where populations may be more vulnerable to environmental impact. We will test the hypothesis that a combination of highly erratic sett ....Living on the edge: settlement dynamics of reef fishes across their ranges. Settlement and early establishment (recruitment) are major determinants of population viability of marine organisms, and can vary greatly among oceans and latitudes. We will compare the recruitment dynamics of populations of reef fishes across their range, including at range boundaries where populations may be more vulnerable to environmental impact. We will test the hypothesis that a combination of highly erratic settlement, poor physiological condition of incoming larvae, and poor recruit growth and survivorship will occur at range boundaries. Outcomes of the study will help in prediction of the viability of fish populations which will improve their management and protection.Read moreRead less