Linking fish recruitment and habitat use to ecosystem processes. Estuaries are transition zones between fresh and marine waters and form key nursery areas for fisheries. Understanding what makes an estuary a nursery area, and how dependent fish are on estuaries, is difficult because we lack vital information on fish recruitment and migrations. We will utilise chemical and genetic techniques to determine patterns of recruitment and migration of fish and link these patterns to biological character ....Linking fish recruitment and habitat use to ecosystem processes. Estuaries are transition zones between fresh and marine waters and form key nursery areas for fisheries. Understanding what makes an estuary a nursery area, and how dependent fish are on estuaries, is difficult because we lack vital information on fish recruitment and migrations. We will utilise chemical and genetic techniques to determine patterns of recruitment and migration of fish and link these patterns to biological characteristics of fish and physical variables of surrounding landscapes. Outcomes will provide managers with key landscape attributes than require conservation. Such information is vital for continued sustainability of fish and estuarine resources and will benefit rural coastal communities.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
Establishing an ecological basis for stocking density of Australian bass in freshwaters: Experimental field tests of a general numerical model. Large numbers of the Australian public go fishing, particularly in rivers and impoundments. Angling in these waterways provides a strong source of income for rural and regional communities. The stocking of native fish to support inland angling also sustains much of the aquaculture industry in western NSW and Queensland. This study will develop an optimal ....Establishing an ecological basis for stocking density of Australian bass in freshwaters: Experimental field tests of a general numerical model. Large numbers of the Australian public go fishing, particularly in rivers and impoundments. Angling in these waterways provides a strong source of income for rural and regional communities. The stocking of native fish to support inland angling also sustains much of the aquaculture industry in western NSW and Queensland. This study will develop an optimal approach to stocking Australian bass which is relevant for other stocked freshwater species, and will allow stocking to be undertaken in an environmentally responsible manner. This will both enhance the outcome of investment of public funds in stocking, and enhance the recreational fishing experience that is so important to rural regional communities.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
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
The importance of edge effects in determining the value of seagrass landscapes as fish nurseries. Seagrasses are a conspicuous element of Australian marine environments, and are crucial in the conservation and maintenance of biodiversity. Degradation of seagrass ecosystems from climatic extremes, increased sediment and nutrients in the water, and other pollutants results in loss and fragmentation of meadows. These changes to seagrass are linked with increased coastal erosion, severe loss of bio ....The importance of edge effects in determining the value of seagrass landscapes as fish nurseries. Seagrasses are a conspicuous element of Australian marine environments, and are crucial in the conservation and maintenance of biodiversity. Degradation of seagrass ecosystems from climatic extremes, increased sediment and nutrients in the water, and other pollutants results in loss and fragmentation of meadows. These changes to seagrass are linked with increased coastal erosion, severe loss of biodiversity, and collapse of fisheries. Increased understanding of how biological processes such as predation and food availability influence animal associations with seagrasses, and how these effects change with landscape structure, will have important applications in the sustainable management of Australia's threatened coastal habitats.Read moreRead less
Using larval connectivity to inform marine reserve network designs in the Coral Triangle. Networks of no-take marine reserves are considered critical tools to ensure conservation and food security targets in the Coral Triangle Region, just north of Australia. More than 1400 community-managed marine reserves have been established in the Philippines, the most populace part of the Coral Triangle. The local conservation and fisheries benefits of these reserves have been well documented. A need now e ....Using larval connectivity to inform marine reserve network designs in the Coral Triangle. Networks of no-take marine reserves are considered critical tools to ensure conservation and food security targets in the Coral Triangle Region, just north of Australia. More than 1400 community-managed marine reserves have been established in the Philippines, the most populace part of the Coral Triangle. The local conservation and fisheries benefits of these reserves have been well documented. A need now exists to convert these individual reserves into operational reserve networks. This project proposes to use new information on larval connectivity, biodiversity and human usage patterns, and local governance networks, to systematically improve the design of an existing Philippine reserve network. 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
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
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.