Objectives: 1. Maintain the interest of tuna fishermen in the tagging program to encourage the return of tags from SBT caught in 1986/87; 2. To "flush out" tags from fish that were caught in previous years, but for some reason were not returned
Population Structure Of The Patagonian Toothfish, Dissostichus Eleginoides, In Australian Waters
Funder
Fisheries Research and Development Corporation
Funding Amount
$71,219.00
Summary
Resolution of stock structure of toothfish in Australian and other waters is required. Tagging experiments, while important, cannot by themselves give a complete picture of stock structure. If genetic differences between areas are detected, then the amount of gene flow between areas must be minimal and more than one stock can be assumed. However, if differences are not detected, then the hypothesis of a single genetic stock cannot be rejected. This hypothesis may be rejected if there is no evide ....Resolution of stock structure of toothfish in Australian and other waters is required. Tagging experiments, while important, cannot by themselves give a complete picture of stock structure. If genetic differences between areas are detected, then the amount of gene flow between areas must be minimal and more than one stock can be assumed. However, if differences are not detected, then the hypothesis of a single genetic stock cannot be rejected. This hypothesis may be rejected if there is no evidence from tagging experiments of fish movement between areas. Therefore, resolution of stock structure is better managed by a combination of tagging and genetic approaches than by either approach alone. Tagging experiments are under way; we propose to carry out the required genetic analyses, and then consider both sets of data jointly to define likely stock structures.
Genetic evidence already collected (based on small sample sizes from two areas of Macquarie), suggests that the amount of movement between fishing locations might be very limited. If this preliminary conclusion is substantiated by larger sample sizes, then careful management of the fishery will be needed, as depletion of one area is unlikely to be quickly replaced by immigration from another area.
The work proposed here will resolve this issue for Macquarie island, and will also determine whether there are separable substocks of toothfish around HIMI, and whether the HIMI stock(s) are separable from the Macquarie island stock(s). Importantly, if William's Ridge fish are identified as part of a straddling stock extending into Australia's EEZ (Heard Island), then they can be managed as though wholly part of Australia's EEZ (recent UNIA agreement).
These issues have to be resolved for effective and sustainable management of toothfish fisheries by Australian management (AFMA). The information gathered will also be relevant to the management authorities of other nations controlling toothfish fisheries.
Note: Recent meetings of CCAMLR (1998, 1999) have recognised the urgent requirement of further work on stock structure in D. eleginoides , particularly as initial genetic studies in other laboratories using isolectric focussing and allozyme analysis have reported inconsistent results (see Box 1 below). Objectives: 1. To use microsatellite variation to resolve the genetic connectivity of different spatial and temporal toothfish samples collected from Macquarie Island and Heard, McDonald Islands. 2. To compare genetic and tagging data from Macquarie and Heard, McDonald regions to maximise toothfish stock structure knowledge in these regions. 3. To report on the outputs from the research and the resultant management response. Read moreRead less
A Study Of The Movement And Behaviour Of The Sand Crab (Portunus Pelagicus) Using Ultrasonic Tags
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Develop ultrasonic tags suitable for tracking & monitoring behaviour of sand crabs. 2. Develop simple methods of tracking tagged free-ranging crabs in Moreton Bay. 3. Obtain positional & Behavioural information over 24-hour periods to map movement of individual crabs
Optimisation Of Feed Distribution To Salmon In Sea-cage Culture
Funder
Fisheries Research and Development Corporation
Funding Amount
$50,314.00
Summary
Objectives: 1. To identify the diel and circannual feeding profiles of salmon in relation to fish size 2. To identify the effect of specific environmental conditions on the feeding patterns of salmon 3. Identify the feeding behaviour of salmon 4. To quantify the level of wastage associated with specific feeding techniques
Platinum Partner For The 2012 International Abalone Symposium In Hobart, Tasmania
Funder
Fisheries Research and Development Corporation
Funding Amount
$20,000.00
Summary
The International Abalone Symposium is a meeting held every three years and is a key activity for the International Abalone Society (http://internationalabalonesociety.org/). The Society is an international forum that aims to promote research on abalone and cooperation between researchers, managers and members of the abalone industries.
The International Abalone Symposium returns after 18 years to Tasmania - home of the world's largest wild abalone fishery. The 8th IAS meeting (May 20 ....The International Abalone Symposium is a meeting held every three years and is a key activity for the International Abalone Society (http://internationalabalonesociety.org/). The Society is an international forum that aims to promote research on abalone and cooperation between researchers, managers and members of the abalone industries.
The International Abalone Symposium returns after 18 years to Tasmania - home of the world's largest wild abalone fishery. The 8th IAS meeting (May 2012) will continue the tradition of bringing together a diversity of international people with one common interest; abalone. The meeting will be designed to encourage engagement and interaction between commercial fishers and growers, managers and policy makers, processors and marketers, and researchers from numerous disciplines.
The IAS2012 program (http://www.cdesign.com.au/ias2012/) will endeavor to address issues of global importance, commercial relevance and scientific interest in Themes that include - Aquaculture, Biotechnology, Climate Change, Conservation, Fisheries, Health, Markets, Post-harvest, Re-seeding and stock enhancement, and Spatial management.
Key to bringing the IAS meeting to Australia in 2012 was to showcase the Australian industries and research, and to revitalize the international interest in abalone fisheries and conservation.
Australian representation and participation at previous symposia has included representatives from the commercial fishers, farmers, processors, managers and researchers. Holding the 8th IAS meeting in Australia will provide an opportunity for a greater proportion of the Australian abalone community to participate and learn, and to better understand the international industries. Support through this project will contribute to the success of the 8th IAS meeting and encourage higher participation by members of the Australian abalone community.
Objectives: 1. Platinum sponsorship of the 8th International Abalone Symposium in Hobart, May 2012 Read moreRead less
Determining Genetic Stock Structure Of Bigeye Tuna In The Indian Ocean Using Mitochondrial DNA And DNA Microsatellites.
Funder
Fisheries Research and Development Corporation
Funding Amount
$88,398.00
Summary
This proposal was developed in response to a call from WCTBFMAC for research into the population structure of bigeye tuna stocks exploited in the west coast tuna fishery. The longline fishery for bigeye tuna off the western coast of Australia is a rapidly expanding fishery due to the high export value of this species. information regarding the stock structure of bigeye tuna is vital for the long term sustainability of the fishery. Uncertainty regarding bigeye stock struc ....This proposal was developed in response to a call from WCTBFMAC for research into the population structure of bigeye tuna stocks exploited in the west coast tuna fishery. The longline fishery for bigeye tuna off the western coast of Australia is a rapidly expanding fishery due to the high export value of this species. information regarding the stock structure of bigeye tuna is vital for the long term sustainability of the fishery. Uncertainty regarding bigeye stock structure seriously restricts the confidence that scientists and fisheries managers can place in the regional assessments that have been carried out to date. At a national or sub-regional level, fisheries managers need to have a better idea of the broader surrounding population of bigeye from which the fish in their fisheries are drawn. In fact, knowledge of the stock structure of bigeye tuna in the eastern Indian Ocean has been listed as the number one priority of the Western Coast Tuna and Billfish Management Advisory Committee. Objectives: 1. To carry out a pilot study into the genetic stock structure of bigeye tuna in the Indian Ocean aimed at determining whether fish from four locations (Western Australia, South Africa, Seychelles, and Indonesia) are drawn from a common gene pool or whether they represent reproductively isolated spawning populations. 2. To compare this Indian Ocean data with data already being collected for the Atlantic Ocean and western tropical Pacific Ocean to gain a broader understanding of the global population structure of bigeye tuna. 3. Should evidence of large scale stock structuring within the Indian Ocean be evident, then a more extensive study will be proposed to indicate the number and extent of the different stocks within the Indian Ocean. This study will likely take the form of a two year proposal. It will attempt to confirm temporal stability of markers and resolve finer population structure by examination of more loci, additional sample locations, and an increased numbers of individuals sampled per location. Read moreRead less
Estimation Of Mortality Rates From Tagging Data For Pelagic Fisheries: Analysis And Experimental Design
Funder
Fisheries Research and Development Corporation
Funding Amount
$179,061.00
Summary
Data from conventional tagging experiments have been and are becoming increasingly important for providing estimates of mortality rates in the stock assessment of large pelagic fishery resources as they provide a powerful, and perhaps only, alternative to relying on CPUE indices of abundance. There is an extensive scientific literature on tag-recapture experiments; however, a comprehensive framework for the analysis and design of tagging experiments in the pelagic fishery context does not exist. ....Data from conventional tagging experiments have been and are becoming increasingly important for providing estimates of mortality rates in the stock assessment of large pelagic fishery resources as they provide a powerful, and perhaps only, alternative to relying on CPUE indices of abundance. There is an extensive scientific literature on tag-recapture experiments; however, a comprehensive framework for the analysis and design of tagging experiments in the pelagic fishery context does not exist. This has meant that in the design phase of tagging experiments, it has not been possible to provide scientifically rigorous advice on matters such as the relative tradeoffs between the number of tags to release, the spatial/temporal distribution of tags and the levels of observer coverage (required for estimation of reporting rates and for estimating the size/age distribution of the commercial catches). In addition, a comprehensive analysis of the extensive data from past SBT tagging experiments (particularly those conducted in the 1990s) taking into account all of the major potential sources of heterogeneity has not been completed because of the lack of a comprehensive estimation framework. Thus, the full benefit of the large research investment from these experiments has not been realized. It is also anticipated that conventional tagging programs will be a major future source of assessment information in both the eastern and western tuna fisheries. As such, an appropriate framework for the design and analysis of tagging experiments is needed to ensure that the full value from both past and future experiments is realized. Finally, there is increasing data accumulating from archival tags. There is a need to understand the role, and the relative cost/benefits, that archival tags can contribute to the overall estimation of mortality rates to past and future conventional tagging experiments. Objectives: 1. to provide a robust estimation framework for estimating mortality rates for tuna stocks from conventional tag recapture data including associated confidence intervals 2. to apply the estimation framework to tag recapture data for southern bluefin tuna 3. to utilize the estimation framework to provide guidance in the design of future tagging experiments - in particular to examine the trade-offs between the number of tags released, levels of observer coverage and spatial/temporal distribution of tags Read moreRead less
Physical Effects Of Hauling On Seagrass Beds (stage 2) (an Extension To 95/149)
Funder
Fisheries Research and Development Corporation
Funding Amount
$44,992.34
Summary
In discussions with estuarine hauling crews, it is clear that they avoid landing their nets in areas of dense seagrass. This potentially confounds the results obtained in the survey of the 9 estuaries. Given that we must sample sites where hauling occurs and hence where the nets are landed (logically), there can be at least two ways of interpreting consistent differences in shoot density and/or leaf-lengths between the control and hauled sites. First, the results provide some evidence that ha ....In discussions with estuarine hauling crews, it is clear that they avoid landing their nets in areas of dense seagrass. This potentially confounds the results obtained in the survey of the 9 estuaries. Given that we must sample sites where hauling occurs and hence where the nets are landed (logically), there can be at least two ways of interpreting consistent differences in shoot density and/or leaf-lengths between the control and hauled sites. First, the results provide some evidence that hauling has an impact on seagrass beds. Second, that the results simply reflect industry's choice to land their nets in areas of reduced amounts of seagrass and hence hauling has little or no impact. Clearly, if this project is to make some recommendations regarding the impacts of hauling and hence its management, we should, if at all possible, avoid concluding the research with these 2 alternatives at the centre of debate.
This seemingly intractable situation is not as hopeless as it would first appear. Previous research (e.g. Larkum et al., 1984) has shown that Zostera capricorni undergoes a cycle of growth in the spring and summer months followed by a dieback in the autumn and winter months. Given that the sampling for the survey has already been completed i.e. well prior to the seagrass attaining maximal shoot densities and leaf-lengths, it would be possible to take advantage of this period of enhanced growth to overcome the shortfalls discussed above. To do so would require that the the same sites be sampled again in late summer because if hauling was having an effect on shoot density and/or leaf-length it would be more clearly evident at this time of year. Furthermore, as we would have a baseline dataset we would predict that the change in shoot density and/or leaf-length from time 1 to time 2 would differ at the hauled compared to the control sites This would occur because the growth of the seagrass would be unaffected at the control sites where it would reach maximal shoot densities and leaf-lengths compared to the hauled site where it would not.
Clearly, the additional sampling described above would require an extension of the project beyond its current completion date in December, 1996. It is envisaged that a further 6 months would be required to complete the additional work necessary. It is important to note that this increased cost of identifying the potential impacts of hauling on seagrass will better serve the fishing industry as the greater scientific rigor gained will reduce the likelihood that the industry is blamed for changes that are not of its own making. Moreover, this approach would likely be the most cost-effective solution to overcome the potentially confounded result that will stem from the existing sampling. A far more costly solution would be to carry out a large-scale field experiment over a number of years to provide 'Before' and 'After" data for hauled and control sites. Objectives: 1. To identify whether the effects of estuary hauling on seagrass meadows is identifiable at the estuary level. 2. To assess the 'within-estuary' impacts of hauling, if any, on seagrass frond height, density and cover. 3. To interpret the results in relation to known information on the utilisation of the seagrass habitat by fish. Read moreRead less
Development Of Biological Tagging Techniques For Penaeid Prawns
Funder
Fisheries Research and Development Corporation
Funding Amount
$303,749.00
Summary
Objectives: 1. To determine the potential of gene transfer as a method of tagging prawns. 2. To determine whether transposable elements exist in the prawn genome 3. To establish a method of genetic transformation in penaeid prawns 4. To determine whether trace elements accumulated by juvenile prawns remain distinguishable in offshore adult populations 5. To determine the uptake and residence time of selected trace elements in prawn tissues 6. To determine which ....Objectives: 1. To determine the potential of gene transfer as a method of tagging prawns. 2. To determine whether transposable elements exist in the prawn genome 3. To establish a method of genetic transformation in penaeid prawns 4. To determine whether trace elements accumulated by juvenile prawns remain distinguishable in offshore adult populations 5. To determine the uptake and residence time of selected trace elements in prawn tissues 6. To determine which body tissues of prawns best conserve the selected trace elements Read moreRead less