Assessing Short-term Movements Of Western Rock Lobsters By Analysis Of Carbon And Oxygen Isotope Ratios In Their Exoskeleton
Funder
Fisheries Research and Development Corporation
Funding Amount
$33,456.00
Summary
Reporting of visible anchor tags by commercial fishers is believed to be biased in some circumstances. There is therefore a need to develop a fishery independent technique of identifying the origin of migrating whites lobsters so as to address the extent of movements of these animals between management zones, without having to rely on visible tags. Objectives: 1. To investigate the factors affecting the carbon/oxygen isotope composition of the exoskeleton of western rock lobsters ....Reporting of visible anchor tags by commercial fishers is believed to be biased in some circumstances. There is therefore a need to develop a fishery independent technique of identifying the origin of migrating whites lobsters so as to address the extent of movements of these animals between management zones, without having to rely on visible tags. Objectives: 1. To investigate the factors affecting the carbon/oxygen isotope composition of the exoskeleton of western rock lobsters as a location specific chemical signatures for that species. 2. To apply these results as a method for determining the locality and depth (temperature) of a lobsters origin, at the time of its most recent moult. Read moreRead less
Determination Of The Migration Patterns Of Juvenile Southern Bluefin Tuna And Jackass Morwong
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Determine whether or not all juvenile southern bluefin tuna migrate down coast of WA, hence whether Aust fishery based on all or part of each cohort. 2. Validate ageing techniques for adults. 3. Are bays & estuaries in southern Tasmania the sole nursery grounds of jackass morwong?
Tagging Of Southern Blue Fin Tuna Off The Coast Of Australia
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Evaluate yield-per-recruit with various harvesting. Update mortality information. Estimate abundance local exploited sub-populations. 2. Quantify information on age-specific migration patterns for simulation model. Technique for ageing SBT. 3. Structure & integrity of schools; exchange of fish among schools
The Fate Of Adult Australian Salmon (Arripis Trutta Esper) In South Australian Waters
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Determine differential movement patterns of different year classes & relative populations of fish taken in commercial & recreational fisheries by tagging; size & age compositions; 2. relating abundance of SA salmon stocks by aerial survey. 3. Examine reproductive status of older year classes in SA waters
Objectives: 1. Compare kingfish from various localities in eastern Australia to identify differences indicative of separate stocks. 2. Use this information plus tagging data to identify stock structure of east coast yellowtail kingfish and clarify their migrations and biology.
Tagging Studies Of The Blue Endeavour Prawn Metapenaeus Endeavouri
Funder
Fisheries Research and Development Corporation
Summary
Objectives: 1. Examine growth, movements & mortalities of the blue endeavour prawn Metapenaeus endeavouri, using a tag release program. 2. Sample commercial catches to enhance logbook catch & effort data to provide further seasonal and area distributions data for the species
Biology, Management And Genetic Stock Structure Of Mangrove Jack (Lutjanus Argentimaculus) In Australia
Funder
Fisheries Research and Development Corporation
Funding Amount
$418,751.00
Summary
Mangrove jack are an essential component of Queensland recreational and commercial fisheries, and one of the icon species for recreational fishers in tropical rivers and estuaries. Community stocking groups are keen to stock mangrove jack to create recreational fisheries in impoundments and to address perceived declines in natural riverine stocks. Despite this, knowledge of the biology of the species is incomplete and a genetic assessment of population structure has never been attempted. The e ....Mangrove jack are an essential component of Queensland recreational and commercial fisheries, and one of the icon species for recreational fishers in tropical rivers and estuaries. Community stocking groups are keen to stock mangrove jack to create recreational fisheries in impoundments and to address perceived declines in natural riverine stocks. Despite this, knowledge of the biology of the species is incomplete and a genetic assessment of population structure has never been attempted. The efficacious management of natural populations of mangrove jack and the future development of effective stocking programs requires information on all aspects of their life cycle, instream habitat requirements, reproduction and maturation, mortality, recruitment into and emigration from river systems. Managers of wild fish species accept that genetically distinct sub-populations of fish may possess novel genetic, physiological, behavioural and other characters that lead to distinct differences in life-history traits including growth rates, fecundity, disease resistance and abundance (Gold and Richardson, 1998). These differences theoretically contribute to the long-term adaptability, survival and resistance to human-induced or other environmental perturbations and can be jeopardised by inappropriate management. It would be imprudent to proceed with the expansion of stocking and aquaculture programs for this species without a comprehensive knowledge of the genetics of the populations. The genetic study will pre-empt potential conflict between management agencies and commercial and recreational interests. Information from the genetic analysis of the species will provide geographic detail for the sustainable use of the resource across State boundaries. Objectives: 1. Investigate the biology of mangrove jack in coastal rivers including habitat preferences, reproduction, recruitment, and movements 2. Determine the genetic stock structure of mangrove jack in Queensland and other parts of their range Read moreRead less
Objectives: 1. Obtain biological data on population dynamics of pelagic resources of shark, mackerel and tuna in northern Aust waters; 2. use data to more effectively manage Taiwanese fishery which is supported by these resources; 3. examine potential for increased Aust participation
Effects Of Trawling Subprogram: Prawn Fishery Bycatch And Discard Effects On Marine Ecosystem Populations
Funder
Fisheries Research and Development Corporation
Funding Amount
$697,270.00
Summary
1) The ecosystem effects of fishing need to be understood in order to work towards an EBM model for the Spencer Gulf. The South Australian government’s Marine Manager’s Forum has identified Spencer Gulf as the first area in SA for the development of a marine management plan. Better information on impacts of fishing will reduce the reliance of managers on the precautionary principle in developing management plans. 2) The important results from FRDC project 98/225: Prawn fishery by-catch and ....1) The ecosystem effects of fishing need to be understood in order to work towards an EBM model for the Spencer Gulf. The South Australian government’s Marine Manager’s Forum has identified Spencer Gulf as the first area in SA for the development of a marine management plan. Better information on impacts of fishing will reduce the reliance of managers on the precautionary principle in developing management plans. 2) The important results from FRDC project 98/225: Prawn fishery by-catch and discards: fates and consequences for a marine ecosystem, are an understanding of the major components of the food chain in the trawled areas of the Gulf and the identification of the major scavenger groups on discarded by-catch. There is a need to obtain data on population impacts in order to develop trophic dynamic models. 3) A prerequisite for energy-flow models is population data outlining life history parameters, growth, migration and immigration and standing stock of, in principle, all the major species. 4) Previous research by this investigator shows that the quantitatively important scavengers on discarded by-catch in the Spencer Gulf prawn fishery are Degens leatherjackets, sealice (non-parasitic highly aggressive isopods and amphiopods), blue crabs, large stingrays and Port Jackson sharks. The effects of discarded by-catch on the population structure of these species need to be understood with the aim of developing an ecosystem model. 5) The impact of fishing on marine ecosystems (target and by-catch) on sharks, skates and rays is a world-wide problem (Stevens et al. 2000). 50% of the global catch is taken as by-catch. The catch of non-target species can have an impact at the population and ecosystem levels, particularly the removal of top predators. Elasmobranchs are at the top of the food chain in the Spencer Gulf and are important by-catch in the prawn fishery. The ecosystem level effects of fishing on the populations of these species are unknown. Discarded by-catch is susceptible to mortality. This mortality, including sub-lethal effects and post discard mortality, needs to be measured in order to predict ecosystem effects. 6) To adopt the principle of ecological sustainability in the prawn fishery, change negative public perceptions of environmental impacts, and improve fishing practices. 7) To enhance the research capacity in environmental research with emphasis on biological resource utilisation. (Stevens, J.D., Bonfil, R., Dulvy, N.K. & P.A. Walker 2000. The effects of fishing on sharks, rays, and chimaeras (chondrichthyans), and the implications for marine ecosystems. ICES J. Mar. Sci. 57: 476-494.)
Objectives: 1. To obtain measurements of the trawling catchability and poplulation parameters of important by-catch and scavenger species particularly including smaller sharks, skates and rays. 2. To determine survival rates of key by-catch species using measures of physiological stress and mortality associated with capture and handling. 3. To determine whether trawling actually attracts or substantially affects the movement of smaller sharks, skates and rays to scavenge on discarded by-catch. 4. To incorporate the results into a marine tropho-dynamic model for sustainable resource utilisation in the Spencer Gulf (EBM). Read moreRead less
Fisheries Biology And Interaction In The Northern Australian Small Mackerel Fishery
Funder
Fisheries Research and Development Corporation
Funding Amount
$486,531.00
Summary
Objectives: 1. Determine whether the Australian spanish mackerel resource, comprising four main species of the genus Scomberomorous, is exploited recreationally and commercially in three distinct areas of tropical Australia, in each of which the stock of each species is an autonomous stock 2. To determine if the species composition of the resource is the same in the 3 areas 3. To determine if the three unit stocks of search of the 3 smaller species differ as to growth rate, repro ....Objectives: 1. Determine whether the Australian spanish mackerel resource, comprising four main species of the genus Scomberomorous, is exploited recreationally and commercially in three distinct areas of tropical Australia, in each of which the stock of each species is an autonomous stock 2. To determine if the species composition of the resource is the same in the 3 areas 3. To determine if the three unit stocks of search of the 3 smaller species differ as to growth rate, reproductive potential or survival rate under average environmental conditions or in consequence in composition as to sex age and size 4. To determine if the resultsobtained from Deuel surveys will be sufficient basis for allocating fishery access as between commercial and recreational fishers 5. To determine if the Deuel special survey method can yield a reliable estimate of the amount of the fishing for the small mackerels by commercial and recreational fishers in remote regions of northern Australia. Read moreRead less