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
The Origin Of Recruits To The East Coast Yellowfin Tuna Fishery And The Delineation Of The Structure Of Yellowfin Stocks In The Western Pacific
Funder
Fisheries Research and Development Corporation
Funding Amount
$549,631.19
Summary
Objectives: 1. To develop the use of microsatellites for the genetic analysis of yellowfin tuna 2. To determine the genetic relationships of yellowfin tuna form the Coral Sea To those from the east coat of Australia and to those from other Western Pacific fisheries 3. To develop techniques for estimation of oxygen 18/16 isotopic ratios in otoliths using SIMS microprobe 4. Using analysis of otolith chemistry and isotopic ratios examine the hypothesis that all recruits to th ....Objectives: 1. To develop the use of microsatellites for the genetic analysis of yellowfin tuna 2. To determine the genetic relationships of yellowfin tuna form the Coral Sea To those from the east coat of Australia and to those from other Western Pacific fisheries 3. To develop techniques for estimation of oxygen 18/16 isotopic ratios in otoliths using SIMS microprobe 4. Using analysis of otolith chemistry and isotopic ratios examine the hypothesis that all recruits to the ECTUNA fishery are derived from spawning grounds in the Coral Sea 5. In the event of rejection of the null hypothesis that there is a single panmictic WP stock, use otolith chemical data collected from yellowfin collected throughout WP to estimate the proportion of immigrant recruits and determine their most likely origin Read moreRead less
Assessment Of Juvenile Eel Resources In South-east Australia
Funder
Fisheries Research and Development Corporation
Funding Amount
$279,545.00
Summary
Objectives: 1. To characterise and qualitatively assess A. australis glass eel migration into coastal catchments of southern NSW, Victoria and Tasmania for the purpose of investigating potential for commercial exploitation of glass eels on an ecologically sustainable basis. 2. To adapt intensive/semi-intensive, pond/tank culture technology for the purpose of enhancing survival and viability of translocated juvenile eels, including glass eels, to be used in restocking/extensive producti ....Objectives: 1. To characterise and qualitatively assess A. australis glass eel migration into coastal catchments of southern NSW, Victoria and Tasmania for the purpose of investigating potential for commercial exploitation of glass eels on an ecologically sustainable basis. 2. To adapt intensive/semi-intensive, pond/tank culture technology for the purpose of enhancing survival and viability of translocated juvenile eels, including glass eels, to be used in restocking/extensive production and/or intensive production to market size. Read moreRead less
Assessment Of The Impacts Of Hydro-electric Dams On Eel Stocks In Tasmania And An Evaluation And Assessment Of Mitigation Strategies
Funder
Fisheries Research and Development Corporation
Funding Amount
$282,684.00
Summary
Stock enhancement strategies can be a cost-effective means of restoring or maintaining fisheries, and have proven essential in catchments with barriers to migration (Knights and White 1998). Regulation of natural river systems has obstructed eel migration in many catchments, and with the implementation of appropriate management tools such as fish passes / ladders and translocation through trapping / netting programs, restoration of stocks can be achieved. Such strategies have not only proven s ....Stock enhancement strategies can be a cost-effective means of restoring or maintaining fisheries, and have proven essential in catchments with barriers to migration (Knights and White 1998). Regulation of natural river systems has obstructed eel migration in many catchments, and with the implementation of appropriate management tools such as fish passes / ladders and translocation through trapping / netting programs, restoration of stocks can be achieved. Such strategies have not only proven successful in increasing commercial fishery yields, but also contribute to enhanced spawning stocks and increased silver eel escapements.
Hydro electric operations (dams and power generating turbines) reduce the chance of successful emigration of silver eel, especially for larger female eel (Dekker 1999), and, depending on flow and turbine type and number, may represent a major source of mortality to pre-spawning adults (Ritter et al 1997).The design of downstream passage ways and the use of non-generating periods to reduce mortality have been trialled and implemented in New Zealand, the USA and Europe, but have yet to be adopted or investigated in Australia.
The sustainability of the eel resource in Tasmania and of existing (and potentially new) commercial eel fisheries in hydro-impounded catchments will ultimately depend on the implementation of appropriate and effective mitigation strategies (passage and/or translocations) specific to both upstream and downstream migrations.
This proposed program addresses the issue of sustainability by assessing both cause and effect of impacts and various mitigation options. It is envisaged that the results and recommendations arising from this proposed study will underpin the development of an integrated management strategy for managing eel fisheries in hydro-impacted catchments with direct benefits to managers and industry alike. Results from this study could be readily transferred to other States, with coordination and dissemination through the existing Australian and New Zealand Eel Reference Group (ANZERG).
REFERENCES
Dekker, W. 1999. Effects of Transfers and Restocking of Eel. Report of the EIFAC Working Group on Eels - Denmark, September 1999. Pp13-17.
Knights, B. and E. White, 1998. An appraisal of stocking strategies for the European eel, Anguilla anguilla - In Cowx, I.G. (ed): Stocking and Introduction of Fish. Fishing News Books. Pp 121-140.
Ritter, J.A., Stanfield, M. and Peterson, R.H. 1997. The American Eel in Eastern Canada - Stock Status and Management Strategies. Proceedings of Eel Workshop January 13-14 1997, Quebec City, QC. Can. Tech. Report 2196. 174p. Objectives: 1. To assess the impacts of hydro-electric dams on eel migrations and eel population structure in Tasmania’s lakes and rivers and to assess the impact of past elver restocking practices in hydro-impounded catchments on eel populations within those catchments. 2. To assess the direct impacts of hydro-electric dams and associated operations (turbine intakes and water management practices) on adult ‘silver’ eel survival rates during their downstream spawning migrations 3. To evaluate various management tools (ladders / bypasses and passage; netting / trapping and translocation) to mitigate impacts and provide recommendations for implementation. 4. To review the management of barriers to eel migration, including overseas experience. Read moreRead less
Stock Structure Of Australian Populations Of Orange Roughy Using Microsatellite Analyses
Funder
Fisheries Research and Development Corporation
Funding Amount
$32,100.00
Summary
Despite the past studies, the question of the stock structure of Australian orange roughy remains unresolved. Broadly, the evidence supports the concept of somewhat localised stocks although with some inter-stock migration - it is really the extent of the migration that remains unknown.
Current management plans are largely based on the premise that southern Tasmanian fish are from a distinct stock from St Helens Hill fish, yet evidence in favour or opposing this proposition is weak. .... Despite the past studies, the question of the stock structure of Australian orange roughy remains unresolved. Broadly, the evidence supports the concept of somewhat localised stocks although with some inter-stock migration - it is really the extent of the migration that remains unknown.
Current management plans are largely based on the premise that southern Tasmanian fish are from a distinct stock from St Helens Hill fish, yet evidence in favour or opposing this proposition is weak.
We propose here an analysis of the stock structure of Australian orange roughy based on the examination of DNA microsatellites. DNA microsatellites will enable a more powerful analysis of genetic stock structure than has hitherto been possible. The study will focus on the relationships of fish from eastern Australia (New South Wales, St Helens Hill, southern Tasmania) but will also examine samples from the Tasman Sea (in particular Lord Howe Rise), New Zealand, and, as a presumably reproductively isolated population, the North Atlantic. Objectives: 1. To develop DNA microsatellite genetic markers for orange roughy 2. To use these markers to delineate stocks of orange roughy from Australian waters 3. To use these markers to compare Australian samples with New Zealand samples. 4. To use these markers to compare North Atlantic samples with Australasian samples Read moreRead less
Adult Migration, Population Replenishment And Geographic Structure For Snapper In South Australia
Funder
Fisheries Research and Development Corporation
Funding Amount
$109,089.00
Summary
Management of the snapper fishery of South Australia has recently attained a level of heightened political sensitivity, reflecting the need to optimise the strategic approach. Nevertheless, from relevant discussions it is apparent that our understanding of the life-history is too poor to predict likely outcomes from suggested regional management strategies.
For this snapper fishery there is a need to optimise management based on a better understanding of the life-history and population ....Management of the snapper fishery of South Australia has recently attained a level of heightened political sensitivity, reflecting the need to optimise the strategic approach. Nevertheless, from relevant discussions it is apparent that our understanding of the life-history is too poor to predict likely outcomes from suggested regional management strategies.
For this snapper fishery there is a need to optimise management based on a better understanding of the life-history and population biology, particularly with regard movement patterns of adult fish. It is currently unknown the extent to which fish move between different geographic regions, and thus the extent to which such behaviour contributes to the natural processes of sustaining the different regional populations. Such adult movement will determine the extent to which regional populations are independent, discrete, and separate sub-populations. Adult movement and stock structure are fundamental to identifying the appropriate spatial scale at which the population dynamics work, and thus the appropriate spatial scale at which fishery management should be applied.
Objectives: 1. to determine whether adult fish from Spencer Gulf, Gulf St. Vincent and other regions migrate to the continental shelf, and where such fish then migrate in order to spawn - do they return to their regions of origin or is subsequent movement determined by other exogenous factors ? 2. to determine the stock structure - does the South Australian snapper population constitute a single, large, inter-mixed population or is it divisible into numerous discrete sub-populations ? 3. to determine whether adult fish collected from particular regions originate as juveniles from those regions or whether they constitute a mixture from different regions. 4. to produce a final report that synthesises all information on snapper movement and stock structure in South Australia, including that from this study on otolith microchemistry with that from tagging studies and work on the analysis of genetics. 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?
Residence Times, Exchange Rates, Migration Patterns And Behaviour Of Black Marlin In The NW Coral Sea: A Pilot Study To Evaluate Interaction Between Recreational And Commercial Fishing Sectors In Area E
Funder
Fisheries Research and Development Corporation
Funding Amount
$127,158.00
Summary
A better understanding of the distribution and migration patterns of marlin and the environmental and biological parameters that determine it, together with an evaluation of the nature and extent of the interaction between the recreational and commercial fleets within Area E, is one of the Eastern Tuna MAC’s top research priorities. This pilot study will provide fine-scale movement data in the recreational fishing areas, and evaluate PSTATs in providing the detailed information on movement dynam ....A better understanding of the distribution and migration patterns of marlin and the environmental and biological parameters that determine it, together with an evaluation of the nature and extent of the interaction between the recreational and commercial fleets within Area E, is one of the Eastern Tuna MAC’s top research priorities. This pilot study will provide fine-scale movement data in the recreational fishing areas, and evaluate PSTATs in providing the detailed information on movement dynamics of black marlin critical to any evaluation of the interaction between the two fisheries. Only when this information is available, will it be possible to incorporate movement dynamics, oceanographic models of circulation in the Coral Sea, and the operational characteristics of the charter and longline fleets into a model to evaluate the availability of black marlin to the charter fleet under different levels of longline effort within Area E. Objectives: 1. Evaluate the local interaction between recreational and commercial fisheries in Area E by using pop-up radio tags to determine short-term movements and residence times of black marlin in the recreational/charter fishery. 2. Evaluate pop-up satellite transmitting archival tags as a cost effective method for obtaining information on large scale movements, exchange rates and residence times of black marlin for assessing fishery interactions on the scale of the NW Coral Sea. Read moreRead less
Tactical Research Fund: Evaluating The Impact Of Fishing On Marine Turtles Relative To Other Impacts
Funder
Fisheries Research and Development Corporation
Funding Amount
$75,000.00
Summary
There is a need to investigate the stock status of turtles, the causes of turtle mortality and to evaluate management options in Commonwealth fisheries based on the estimated fishing mortality of turtles.
The impetus is coming from various conservation and fisheries agreements and there have been many resolutions issued by expert-based bodies calling for a worldwide reduction in turtle captures by commercial fisheries. Requirements to protect marine species under the EPBC Act has impose ....There is a need to investigate the stock status of turtles, the causes of turtle mortality and to evaluate management options in Commonwealth fisheries based on the estimated fishing mortality of turtles.
The impetus is coming from various conservation and fisheries agreements and there have been many resolutions issued by expert-based bodies calling for a worldwide reduction in turtle captures by commercial fisheries. Requirements to protect marine species under the EPBC Act has imposed high standards upon fishing activities in Australian waters, with increased attention to the need for better data collection and bycatch management witnessed in the Bycatch Action Plans. The Australian Sea Turtle Recovery Plan also documents the importance of addressing sea turtle bycatch issues by commercial fisheries.
There is an economic incentive to minimise sea turtle bycatch. Evidence suggests that the ETBF may have what U.S. authorities consider a significant-take of turtles. Following a range of restrictions placed on U.S. domestic longliners, including fishery closures, there have been calls for the extension of their domestic law to other nations. Australia’s ability to pre-empt or respond to any threat of trade action is vital in light of the real probability of trade measures such as import embargoes.
The NPF adopted TEDs many years ago and now there is a need to review that measure as the principal mitigation measure. A further current need is to explore changes made to other prawn trawl fisheries around the world with respect to TEDs and turtle mitigation. These comments also apply equally to the East Coast Trawl.
This approach may ultimately benefit Australian commercial fisheries by possibly leading to a reduction in the impact of their fisheries on the ecosystem and reduce the probability of negative impacts through unilateral trade actions for longline fisheries and public backlash for many commercial fisheries.
Objectives: 1. Review the literature regarding existing research on spatial distribution and causes of mortality in the Eastern Tuna and Billfish Fishery(ETBF), Western Tuna and Billfish Fishery (WTBF), Northern Prawn Fishery (NPF), and East Coast Trawl. 2. Review the literature regarding management and mitigation measures currently in place. 3. Analyse turtle distribution and movement patterns and overlap with fishing distribution. Estimate mortality resulting from interactions. 4. Review relevant turtle stock assessments and report on all known anthropogenic impacts on turtle mortality. 5. Assess alternative management options to respond to the estimated level of turtle mortality. 6. Identify research gaps needed to inform fisheries management options to mitigate turtle interactions in these fisheries. Read moreRead less