Testing the Flood Pulse Concept for rivers with variable flow regimes. For floodplain rivers the major unifying conceptual model linking hydrology, biogeochemistry and ecology is the Flood Pulse Concept (FPC). The model is based on rivers that have a seasonally predictable and long duration inundation of floodplain habitats. Recent reviews of the FPC indicate that the model needs to be broadened to describe the function of rivers with more variable flow regimes. This project will test some of th ....Testing the Flood Pulse Concept for rivers with variable flow regimes. For floodplain rivers the major unifying conceptual model linking hydrology, biogeochemistry and ecology is the Flood Pulse Concept (FPC). The model is based on rivers that have a seasonally predictable and long duration inundation of floodplain habitats. Recent reviews of the FPC indicate that the model needs to be broadened to describe the function of rivers with more variable flow regimes. This project will test some of the predictions of the FPC for variable dryland rivers by investigating how food webs in the channels of a floodplain reach respond to flows of different magnitude, seasonal timing and duration.Read moreRead less
MICROSCALE PLANKTON AND PARTICLE DYNAMICS: COMPARING AND CONTRASTING AUSTRALIAN AND INTERNATIONAL SEAS. Microscopic phytoplankton are the basis of ocean ecosystems, but most predictions and measurements focus on processes that occur over kilometres. Our recent work shows that definite and regular submetre seascape topography exists. This grant will test the extent to which this seascape topography is the fundamental organisational unit of marine ecosystems and the extent to which it characteris ....MICROSCALE PLANKTON AND PARTICLE DYNAMICS: COMPARING AND CONTRASTING AUSTRALIAN AND INTERNATIONAL SEAS. Microscopic phytoplankton are the basis of ocean ecosystems, but most predictions and measurements focus on processes that occur over kilometres. Our recent work shows that definite and regular submetre seascape topography exists. This grant will test the extent to which this seascape topography is the fundamental organisational unit of marine ecosystems and the extent to which it characterises Australian coastal waters and open ocean water masses. This research takes a leadership role in defining and advancing our understanding of how marine ecosystems function. The project will bring over $200 million of Japanese infrastructure to Australia for 3 years.Read moreRead less
A Quantitative Analysis of Prawn Harvesting Strategies. Prawn fisheries in NSW are undergoing major changes in their management. This unusual PhD project will design and test new decision-rules and strategies for fishery managers that are based upon pragmatic quantities of catch-per-unit-effort, prawn size, and river temperature and discharge. The performance of rules and strategies will be measured to ensure that they generate satisfactory outcomes for the prawn resources and the people that de ....A Quantitative Analysis of Prawn Harvesting Strategies. Prawn fisheries in NSW are undergoing major changes in their management. This unusual PhD project will design and test new decision-rules and strategies for fishery managers that are based upon pragmatic quantities of catch-per-unit-effort, prawn size, and river temperature and discharge. The performance of rules and strategies will be measured to ensure that they generate satisfactory outcomes for the prawn resources and the people that depend upon them. A major outcome will be precautionary or risk-averse decision-rules and strategies that are robust to the uncertainties that exist in prawn fisheries.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
What drives recruitment variability in Snapper? Application of a novel theoretical and empirical approach to predict fluctuations in fisheries. This research will contribute to the sustainable management of the snapper resource to both protect the population and also provide long-term sustainability in terms of the ecosystem goods and services provided by the fishery, and associated social and economic benefits. Results will have broad applicability, as the critical environmental factors identif ....What drives recruitment variability in Snapper? Application of a novel theoretical and empirical approach to predict fluctuations in fisheries. This research will contribute to the sustainable management of the snapper resource to both protect the population and also provide long-term sustainability in terms of the ecosystem goods and services provided by the fishery, and associated social and economic benefits. Results will have broad applicability, as the critical environmental factors identified are likely to influence other species as well. Understanding the environmental factors underpinning recruitment variation in snapper will allow better predictions of impacts on recruitment levels resulting from climatic variability in the short term, and also longer-term effects of climate change on the population, for incorporation into future management assessments.Read moreRead less
Resilience of Moreton Bay to climate change: Links between nutrient inputs and plankton dynamics. A healthy Moreton Bay, with its lucrative fishing, iconic turtles, dugongs and seabirds, helps support the $9 billion per annum tourist industry in SE Queensland. Moreton Bay is under increasing threat from nutrients produced by a mushrooming coastal population and from climate change impacts. Here we investigate nutrient-plankton relationships and develop a simple model to evaluate future impacts o ....Resilience of Moreton Bay to climate change: Links between nutrient inputs and plankton dynamics. A healthy Moreton Bay, with its lucrative fishing, iconic turtles, dugongs and seabirds, helps support the $9 billion per annum tourist industry in SE Queensland. Moreton Bay is under increasing threat from nutrients produced by a mushrooming coastal population and from climate change impacts. Here we investigate nutrient-plankton relationships and develop a simple model to evaluate future impacts on bay health. This project will put Australian scientists at the forefront of research focused on the adaptation of coastal marine environments to climate impacts, and ensure that Moreton Bay remains healthy now and into the futureRead moreRead less
Understanding the stock-recruitment relationship to reverse the decline in the southern rock lobster. Declines in southern rock lobster fisheries across three Australian states show that we need to understand the flow and survival of larvae. The project aims to identify the fundamental links between recruitment and spawning stock, to enable predictions of recruitment for the management of adult stocks, safeguarding the future of the fishery.
Reef Area Estimation And Habitat Typing By Aerial Photography (Project Cancelled)
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Examine the feasibility of aerial photographic techniques for estimation of area and type of underwater rocky bottoms, 2. identification and mapping of abalone and associated macro-algal communities.
The Biology And Ecology Of Blue Grenadier With Particular Reference To Stock Recruitment, Stock Identity And Its Role In A Multispecies Fishery
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Investigating recruitment patterns to stocks using larval & adult fish; no of separate stocks in Tas waters using biochemical genetic techniques 2. relationship between adult blue grenadier & other species, especially mortality from predation & 3. ; influence of food supply on the populations
Linking Fishery-dependent And Fishery-independent Assessments Of Abalone Fisheries
Funder
Fisheries Research and Development Corporation
Funding Amount
$412,571.00
Summary
Abalone stocks are vulnerable to localized depletion, followed by fishery collapse. In Australia, assessments of abalone fisheries have been written in all abalone-producing states. However, except in NSW (Worthington, 1998), the basis for those stock assessments is generally an anecdotal interpretation of un-standardized commercial catch-effort data and, sometimes, information on the size-composition of the catch. This information is often combined, in an informal way, with research data to giv ....Abalone stocks are vulnerable to localized depletion, followed by fishery collapse. In Australia, assessments of abalone fisheries have been written in all abalone-producing states. However, except in NSW (Worthington, 1998), the basis for those stock assessments is generally an anecdotal interpretation of un-standardized commercial catch-effort data and, sometimes, information on the size-composition of the catch. This information is often combined, in an informal way, with research data to give an impression of the status of the stocks. Performance indicators used do not tend to be biologically based. Most importantly, the sustainability of current catch levels is not known with any confidence. Meeting the guidelines from Environment Australia with regard to sustainability of fisheries will require a more formal assessment for such an important fishery.
The development of FRDC project 1999/116, to develop a National Abalone Model, is an attempt to answer the obvious need for a valid model. Currently, New South Wales is the only state where a stock assessment model is being used as the basis for fishery management decisions in an abalone fishery. In Tasmania, The inputs currently available to the model being developed include fishery-dependent catch-effort data, fishery-dependent length-frequency data, research length-frequency data, and estimates of biological parameters. The crucial data, missing from the inputs to the model, is a fishery-independent index of relative abundance. The survey techniques used in NSW and in Victoria have been found incapable of producing estimates with sufficient precision under Tasmanian conditions. There is thus a need to develop an optimum combination of fishery independent indices of abundance that will have application in the full range of Tasmanian abalone habitats. In addition, Tasmania's raw catch-effort data must be standardized prior to its use in a formal assessment model because of the high variability in catch rates between divers, areas, season, and other factors.
Specifically this project will: (1) better determine the relationship between catch-rate and abundance. This is needed for realistic standardisation of catch and effort statistics; (2) improve our understanding of the differences between commercial size-composition data and the actual size composition of the legal size abalone left after fishing (selectivity v availability). Such data are a key ingredient of stock assessment models; (3) assess the accuracy of diver logbook data. This will help ensure that the data requested via industry logbooks focuses on the most appropriate questions and will assist with appropriate standardisation.
The information gained will underpin the development of credible, realistic fisheries models for abalone, which will consequently improve the confidence with which abalone fisheries are managed. Increased confidence in fisheries management decisions will have measurable economic benefits. Objectives: 1. Establish the most appropriate fishery independent, index of relative abundance for a range of abalone habitats in Tasmania. 2. Develop methods of standardizing abalone catch-rate data that best relate catch-rates to abundance. 3. Establish the optimum means for obtaining validated fishery-dependent data. 4. Synthesize all results so they can be included in the abalone stock assessment model currently under development. Read moreRead less