This project will address key aspects from four highly ranked SSJF research priorities as established by SquidRAG in 2005:
1. Understanding spatial distribution and the effects of environmental variability on squid. 2. Entrapment versus attraction, discovering the biological differences between jig and trawl caught squid. 3. Growth, reproduction, mortality and productivity 4. Squid predator-prey relationships
Research needs for the newly proposed tar ....This project will address key aspects from four highly ranked SSJF research priorities as established by SquidRAG in 2005:
1. Understanding spatial distribution and the effects of environmental variability on squid. 2. Entrapment versus attraction, discovering the biological differences between jig and trawl caught squid. 3. Growth, reproduction, mortality and productivity 4. Squid predator-prey relationships
Research needs for the newly proposed targeted mid-water trawl squid fishery for the GAB will also be addressed.
This project also sits squarely within two strategic goals within the FRDC R&D Program 1 Planned Outcome- Natural Resource Sustainability: (1) “To increase and apply knowledge of the biology of fish and their ecosystems” and (2) “To increase and apply knowledge of interactions between fish and their ecosystems”.
Previous research has established important biological parameters for arrow squid, it has also highlighted large temporal and spatial variability. This variability coupled with the extreme fluctuations in fishery production hinders successful management.
Understanding the role the environment plays in arrow squid population dynamics will help develop models and pinpoint periods when conditions are conducive to squid growth and recruitment.
Understanding whether different techniques (jig vs. trawl) target different components of the population is significant especially for future policies on total allowable effort (TAE).
Understanding squid diet is also important for ecosystem management (ie.; especially for the proposed GAB fishery that will also be harvesting potential prey).
It was recognised at the Canberra meeting that Australia does not have the capacity to undertake broad-scale pre-season recruit net surveys, but using both light trapping of recruits and ecosystem modelling were seen as feasible techniques for understanding recruitment and stock fluctuations.
Both the SquidMAC and the SquidRAG see ongoing research as extremely important for future informed management of the fishery. Objectives: 1. To investigate the influence of environmental and oceanographic variables on arrow squid growth and recruitment 2. To investigate the ecology, population dynamics of squid in the newly proposed mid-water trawl GAB fishery 3. To compare the biological composition of jig and trawl-caught squid 4. To describe the key components, spatial and temporal variability and environmental influences on the diet of arrow squid 5. To assess the use of light traps as samplers of juvenile squid recruitment 6. To develop an ecosystem model based on squid predator-prey relationships for squid stock assessment 7. To provide SquidMac with better information on environmental influences on stock fluctutations to assist in determining trigger points for the fishery 8. VARIATION TO CONTRACTOBJECTIVE 5 "To assess the use of light traps as samplers of juvenile squid recruitment" is still an objective of teh project but has been discontinued beacue this method was considered inappropriate as arrow squid were not attracted by the light traps" 9. VARIATION TO CONTRACTOBJECTIVE 3: "To compare the biological composition of jig and trawl-caught squid" Read moreRead less
Tactical Research Fund: Synthesis Of Existing Information, Analysis And Prioritisation Of Future Monitoring Activities To Confirm Sustainability Of The Red-legged Banana Sub-fishery In The Joseph Boneparte Gulf
Funder
Fisheries Research and Development Corporation
Funding Amount
$53,440.00
Summary
The Northern Prawn Fishery (NPF) received certification under the Marine Stewardship Council in 2013, becoming the first tropical prawn fishery in the world to receive ecocertification under this process. Certification was conditional upon a number of actions being addressed. Included among them was the need to demonstrate, using robust scientific information, that fishing in the JBG sub-fishery is not having adverse impacts on at-risk species, vulnerable habitats or ecosystems.
To main ....The Northern Prawn Fishery (NPF) received certification under the Marine Stewardship Council in 2013, becoming the first tropical prawn fishery in the world to receive ecocertification under this process. Certification was conditional upon a number of actions being addressed. Included among them was the need to demonstrate, using robust scientific information, that fishing in the JBG sub-fishery is not having adverse impacts on at-risk species, vulnerable habitats or ecosystems.
To maintain certification under the MSC, NPF Industry Pty Ltd must undertake a number of actions by September 31 2013. They include: - evaluating existing information to confirm its suitability for understanding key ecosystem elements in the JBG, understanding the nature, distribution and vulnerability of main habitat types present, and monitoring at-risk species (where identified). Identify deficiencies/gaps; - implementing a program of activities to address deficiencies/gaps where required; and, - using existing and newly implemented (as required) research and monitoring activities to assess the status of at-risk species, vulnerable habitats and ecosystems in the JBG sub-fishery.
This proposal will seek to progress these actions. Failure to do so would jeopardise ongoing certification of the NPF. Objectives: 1. Determine the feasibility of using and extending the existing observer coverage of the NPF to monitor the at-risk species identified through the ERA process 2. Assess all available spatially-explicit information on habitats and their proxies (seascapes, bioregions, environmental envelopes, geomorphs, etc.), and develop a detailed plan to identify the nature, distribution and vulnerability of main habitat types in the JBG 3. Assess whether existing information available is sufficient to understand key ecosystem elements (including target species, bycatch species and habitats) in the JBG fishery Read moreRead less
The 4th International Fisheries Observer Conference
Funder
Fisheries Research and Development Corporation
Funding Amount
$20,000.00
Summary
By-catch from fishing methods is one of the most significant issues facing the world’s fisheries. Over the past decade or so, researchers in Australia, the US and Canada have been quite successful at reducing some of the more serious by-catch problems, particularly those concerning the huge discarding and wastage problems associated with trawling. Various projects have shown that the most effective way of reducing discards is to follow a staged scientific protocol involving: (i) identifying an ....By-catch from fishing methods is one of the most significant issues facing the world’s fisheries. Over the past decade or so, researchers in Australia, the US and Canada have been quite successful at reducing some of the more serious by-catch problems, particularly those concerning the huge discarding and wastage problems associated with trawling. Various projects have shown that the most effective way of reducing discards is to follow a staged scientific protocol involving: (i) identifying and quantifying by-catches to determine places and times of particularly problematic by-catches and (ii) doing experimental tests of modified fishing practices that reduce the identified by-catches. The ONLY way to achieve the first, quantification stage accurately is to have scientific observers going out on typical fishing trips to record information on catches and discards (these are termed Observer Programmes). Significant advances in identifying and quantifying by-catches have been made in several countries, including Australia, the US and Canada through Observer Programmes. As well as quantifying bycatches and discarding, Observer Programmes have proven invaluable in providing information on levels of compliance of commercial fisheries to regulations and codes of conduct. They also provide excellent material for biological work on species that would otherwise be very expensive or problematic to collect (e.g. gut contents, sizes, age information, otoliths etc.), operational information on fleet dynamics and changes in fishing effort. Such programmes are also increasingly being used as on-deck extension and educational services, teaching fishers first-hand about a range of scientific, compliance and management issues.
In 1998, Fisheries and Oceans Canada and the United States’ NOAA Fisheries sponsored the first of a series of biennial international conferences on Fisheries Observer Programmes. This series of conferences (previously held in Seattle, St. Johns and New Orleans) brings together the key stakeholder groups, scientists, technicians and managers responsible for the design, management and safe delivery of at-sea fisheries observer programs throughout the world. It provides the main international forum to address the many facets of these very important data-gathering programmes. NSW Fisheries has been successful in the bid to host the 4th International Fisheries Observer Conference in Sydney in November 2004.
The hosting of this conference in Sydney has been discussed and endorsed at the last 3 meetings of the AFMF Research Committee. Objectives: 1. To bring together a broad representation from the international fisheries community to address most of the key issues concerning the establishment, execution and use of fisheries observer programs. Read moreRead less
Development And Cost-benefit Analysis Of An Electronic Observer System To Monitored A Remote Small Vessel Commercial Fishery
Funder
Fisheries Research and Development Corporation
Funding Amount
$40,488.18
Summary
Monitoring of remote small vessel fisheries in Australia is often difficult and always costly. Travel costs, observer wages, and operational inefficiencies and restrictions of small vessels in accommodating on-board observers are all factors which act to restrict monitoring coverage while still incurring a relatively high cost to industry. With the a growing need for accurate catch and effort data and the high costs and operational restrictions of using human observers there is a subsequent need ....Monitoring of remote small vessel fisheries in Australia is often difficult and always costly. Travel costs, observer wages, and operational inefficiencies and restrictions of small vessels in accommodating on-board observers are all factors which act to restrict monitoring coverage while still incurring a relatively high cost to industry. With the a growing need for accurate catch and effort data and the high costs and operational restrictions of using human observers there is a subsequent need to find a cost effective alternative that will not only improve coverage levels but also reduce costs. Objectives: 1. To determine if an electronic monitoring system is a feasible alternative to on board observers for species identification, and the quantification of discarded and retained weights in a remote fishery. 2. To determine the full range of costs and benefits of implementing an Electronic Monitoring System. 3. To compare the full range of cost and benefits of an electronic monitoring system with the full range of costs and benefits of on board observers. Read moreRead less
Facilitating Industry Self-management For Spatially Managed Stocks: A Scallop Case Study
Funder
Fisheries Research and Development Corporation
Funding Amount
$300,992.94
Summary
Both the Tasmanian and Commonwealth scallop fisheries are recovering from severe depletion. In an attempt to ensure future sustainability of the fishery, a form of spatial management has been implemented in both jurisdictions, however, specific management protocols are still evolving. This proposal follows naturally from some of the results of FRDC 2003/017, which is investigating some of the management rules used in scallops. One conclusion from 2003/017 will be that the optimal management regi ....Both the Tasmanian and Commonwealth scallop fisheries are recovering from severe depletion. In an attempt to ensure future sustainability of the fishery, a form of spatial management has been implemented in both jurisdictions, however, specific management protocols are still evolving. This proposal follows naturally from some of the results of FRDC 2003/017, which is investigating some of the management rules used in scallops. One conclusion from 2003/017 will be that the optimal management regime for widely dispersed scallop beds is to close most of the fishable area only opening a limited number of beds each year in a rotational fashion. One essential requirement for such management is the need for detailed information about the size and abundance of scallop beds across the entire fishery. Fishery-independent surveys would be far too expensive in a cost-recovery management regime - in Commonwealth waters relatively small surveys have cost at least $45000 to $50000 a year and that would not cover the area now available. Therefore, the only economically viable means of providing this information is to devise some means of encouraging Industry members to collect the necessary information both prior-to and during fishing seasons. Ad hoc trials were attempted in Tasmanian waters in 2003, which led to the identification of many operational problems with such surveys. Once these practical problems have been overcome, credibility and authority also need to be added to such fishery dependent surveys.
The vision of this project is of an on-going Commonwealth and Tasmanian scallop fishery managed at a small spatial scale using information provided by Industry itself in the absence of formal independent observers. Such a vision relies on Industry becoming a vital component of the management, and thus requires the development of protocols to ensure the growth in participation and expertise for industry-run sampling. This vision has still to be developed in detail but reflects the needs and wishes of Industry for better economic returns to fishers, while ensuring the long-term sustainability of the fishery.
If the general principles of such Industry initiatives are developed in the scallop fishery, then other spatially managed fisheries should be able to develop similar regimes, leading not only to better management but greater industry involvement in management. Objectives: 1. Develop a generalized, credible regime of Industry observations to provide the necessary assessment information required to manage a spatially structured fishery. 2. Develop and trial a workable design for a pre-season permit fishery in the Tasmanian and Commonwealth scallop fisheries to provide the information necessary to characterize the stock status in each spatial region of the entire fishery (Size distribution, condition, and possibly abundance). 3. Develop and trial a workable design for within season volunteer Industry survey observations within the Tasmanian and Commonwealth scallop fishery for within season monitoring, comparison with the pre-season survey, and more detailed characterization of the available resource. 4. Develop mechanisms whereby Industry take (foster) ownership over the details of survey design and the organization and funding of such operations, along with how best to generate management advice that is perceived by Industry as unbiased, acceptable to all, and providing maximum return for product landed. 5. Aid the development of a clear vision for the future of the Bass Strait scallop fishery and how it can use spatial management to its own benefit. Read moreRead less
Developing Integrated Performance Measures For Spatial Management Of Marine Systems
Funder
Fisheries Research and Development Corporation
Funding Amount
$805,294.00
Summary
The need to report on the ecologically sustainable use of marine systems, that have been ‘zoned’ at a variety of spatial and temporal scales is gaining considerable support in Australia and world-wide. MPAs and other spatial management arrangements are being introduced in most Australian management jurisdictions through the NRSMPA process and at the Commonwealth level through Regional Marine Planning under Oceans Policy. Clearly, spatial management, particularly expressed as MPAs, is here to s ....The need to report on the ecologically sustainable use of marine systems, that have been ‘zoned’ at a variety of spatial and temporal scales is gaining considerable support in Australia and world-wide. MPAs and other spatial management arrangements are being introduced in most Australian management jurisdictions through the NRSMPA process and at the Commonwealth level through Regional Marine Planning under Oceans Policy. Clearly, spatial management, particularly expressed as MPAs, is here to stay. For example FRDC suggests that nations will set targets such as 20% of the coastal zone for high degrees of protection through MPAs (FRDC R&D Plan 2000-2005).
The objectives of MPAs are usually to achieve ESD for the regional ecosystem and for the various sectoral users of the ecosystem. For example, the benefits to fisheries are often listed to be to increase the spawning biomass, to act as an insurance policy against fishery management errors, to protect critical habitats to damp ecosystem wide fluctuatons and to provide reference sites to be used in fishery resource assessments. However, while some studies have shown that the harvesting regimes for specific areas within a system can change biomass, density, size of organisms, quality of habitats and species diversity, the causes of the extent and nature of these changes at various spatial and temporal scales impedes the selection of performance indicators.
The use of MPAs is a relatively new approach to marine management and is at a very early stage of development. For example the use of other management tools includes the use of performance assessment and the triggering of management responses under different circumstances. In fisheries this is commonly through the periodic review of catch or fishing effort levels in relation to stock condition. The policy descriptions of the use of MPAs and spatial management, for example in Oceans Policy also makes reference to the use of such adaptive management, but the methodology to enable and guide this has not net been developed. This was highlighted at the recent World Congress on Aquatic Protected Areas and FRDC’s workshop on R & D priorities where it was clear that the current state of the science limits the ability for performance assessment.
It is not yet clear under what circumstances specific areas within large systems contribute to the system as a whole, and the way in which large system behaviour influences areas within it . Globally spatial area management, as illustrated by MPAs, is receiving considerable attention as ‘new’ tool to control over-exploitation of fish stocks (eg Pauly et al 2002). In a recent review Ward et al (2000) state that there are “...very few examples where benefits to a fishery (as opposed to the closed area ) have been well studied and documented”. Similar conclusions are being drawn in other reviews currently appearing (e.g. Halpern in press). Socio-economic impacts are even less well studied (Sanchirico 2000).
Without such performance assessment managers and resource users may become locked into sub-optimal management arrangments, and if MPAs and other area management arrangements are not working as intended then achieving goals such as Ecologically Sustainable Development may be unknowingly at risk. Consequently, even with objectives that are clearly defined and agreed by all stakeholders, the most challenging work still remains as how to evaluate performance.
Victoria is committed to range of activities to ensure marine systems are managed for ecological sustainability. Recent initiative include reforms to the management of abalone, rock lobster and the establishment of marine protected areas, these together with National Oceans Office planning for the South-East Region, provides a major opportunity for this work to be undertaken. In addition, the NOO have identified integrating fisheries spatial management and MPAs as an action in the South East Regional Marine Plan.
This project does not address whether or not there should be MPAs rather it is designed to develop an effective means to assess the performance of the system and the MPA within it. We will build on previous work but more importantly extend the scope to include fishery ecosystem considerations as well as direct impacts on target species and biodiversity. Objectives: 1. Through an analysis of monitoring data from existing marine system management egimes (including MPAs) and an identification of observational approaches that are available to be used, develop simple biophysical and management models of impact and response at various spatial scales. 2. Use these models to develop and evaluate measures to report performance for specified management objectives particularly in respect of power to detect change. Read moreRead less
Tactical Research Fund: Workshop To Scope A Longline Trial To Target Gummy Shark In Waters Off SA And Quantify Bycatch And Interactions With TEP And High Risk Species
Funder
Fisheries Research and Development Corporation
Funding Amount
$24,709.58
Summary
At the time of writing this research proposal, many shark gillnet fishermen operating in waters off South Australia are not going out fishing because of the cost of 100% observer coverage (~$1000/day) and because many of their most valuable fishing grounds have been closed to protect Australian Sea Lions. Fishing and onshore businesses that are dependent on the catch of Gummy Shark are suffering extreme financial hardship and some are already up for sale. Although the current AFMA direction may ....At the time of writing this research proposal, many shark gillnet fishermen operating in waters off South Australia are not going out fishing because of the cost of 100% observer coverage (~$1000/day) and because many of their most valuable fishing grounds have been closed to protect Australian Sea Lions. Fishing and onshore businesses that are dependent on the catch of Gummy Shark are suffering extreme financial hardship and some are already up for sale. Although the current AFMA direction may only be in place for 6 months, it is likely to continue in some form, and many fishers cannot see a future for gillnets off SA because of their potential impact on ASLs and the measures that will need to be implemented to protect them. If their businesses are to become viable again and have any future, they need to find another method of targeting gummy shark. Demersal longlines offer that opportunity.
The fishery is now between a rock and a hard place: if it stays with gillnets, it faces an bleak future with concern about ASL and other TEP bycatch requiring, large closures and tighter management; by moving to longlines, ASL bycatch will be negligible but the bycatch of conservation-dependent School Sharks and different TEP species may be an issue as well as concern about high catches of fish targeted by neighbouring fisheries. Also, current management arrangements are critically dependent on the highly size-selective nature of current 6 inch gillnet mesh size which prevents the capture of large mature sharks and hence preserves the breeding population. Whilst it presently has significant opposition, the move to longlines seems the only future for SA gummy shark fishermen. A dedicated research project is required to answer many of the concerns about the use of demersal longlines to target Gummy Shark.
Objectives: 1. Hold a workshop about the potential for longlines to target Gummy Shark in SESSF waters off South Australia. 2. Clarify the issues and concerns of the wide range of stakeholders at the workshop. 3. Develop the detailed design of a longline trial, focusing on trial method, fishing gear and obtaining the information required to help inform stakeholder concerns. Read moreRead less
External Review Of Independent Data Validation Options, Uses And Opportunities
Funder
Fisheries Research and Development Corporation
Funding Amount
$308,754.00
Summary
Introduction Independent data validation in commercial fishing is becoming more commonplace in Australia. Fisheries in Australia provide a significant income to the country, and play an integral role in our food security, livelihoods, and social lives. Challenges such as overfishing, illegal and unreported fishing, bycatch and interactions with threatened, endangered, or protected species, provide hinderances to fully sustainable fishing. The increasing demands on the marine environment for ....Introduction Independent data validation in commercial fishing is becoming more commonplace in Australia. Fisheries in Australia provide a significant income to the country, and play an integral role in our food security, livelihoods, and social lives. Challenges such as overfishing, illegal and unreported fishing, bycatch and interactions with threatened, endangered, or protected species, provide hinderances to fully sustainable fishing. The increasing demands on the marine environment for energy production, marine protected areas, and recreational use are leading management of fisheries in Australia to be spatially based. Currently, some jurisdictions in Australia (e.g. Queensland, Tasmania, Australian Fisheries Management Authority), have already introduced independent data validation programs. The aim of these programs is, on the surface, to improve the quality, reliability, and transparency of fisheries data in Australia. However, there is considerable distrust from commercial fishers regarding a) data collection methods; b) the use of collected data; c) the legality of both collecting, and storing data; d) the cost of installing and running the systems – both financial and physical; e) ongoing maintenance of systems; f) the reliability of data from the systems, and g) whether the data are actually going to be used for their intended purpose. Recognising the need for greater transparency in fisheries data, and the general distrust of these systems, this project aims to provide an external review of data validation options, uses, and opportunities within Australia. Objective The primary objective of this project is to address industry stakeholders’ concerns regarding the reliability and transparency around the collection, use, and storage of independent fisheries data validation methods. This will be achieved by conducting a comprehensive, and systematic review of independent data validation (IDV) processes both within Australia, and globally. The review will then allow us to evaluate IDV mechanisms, legal implications around IDV, and economic considerations of various IDV methods, including whether any value-add opportunities exist. The project will provide outputs that will allow for efficient choice of relevant data validation options for particular fisheries in Australia, while outlining the pros and cons for relevant methods. The results will enhance confidence for commercial fishers, and fishery managers around choosing the best data validation options for their fishery.
Methods 1) Systematic literature review to determine available independent data validation methods We will research and compile a comprehensive list of independent data validation methods (IDV) that are available currently, and in the future through a systematic literature review. The systematic literature review will cover peer-reviewed literature and relevant reports published globally in the last 10 years. The review will examine existing technologies, methodologies, and best practices in IDV used in relevant industries (not just limited to fisheries), and present a summary of current best practice, and likely additions in the future to IDV. The review will include information on the potential add-on possibilities associated with IDV methods – which will be expanded upon in (4). The review will equip industry stakeholders with the knowledge to fully understand the range of options in IDV, and those most suitable for their fishery. 2) Stakeholder consultation – strengths, weaknesses, opportunities, and threats (SWOT) Within the project we will conduct an extensive survey across a diversity of fishers across Australia (including those that have already implemented IDV, and those that have not), to gather insight into the perceptions of independent data validation (IDV). Through this SWOT analysis, we will identify the strengths, weaknesses, opportunities, and threats associated with current IDV mechanisms from the perception of industry, and map this to the published literature in point (1). This will allow us to address concerns from industry and identify those concerns that are representative of IDV globally. This analysis will serve as a foundational understanding of the industry's readiness and receptiveness towards adopting IDV and provide industry with independent information relating to their concerns. 3) Review of legal implications for IDV implementation, including case studies Alongside the systematic literature review in (1), we will conduct a thorough review of Australian legislation relating to IDV. This will include both publicly available legal documents, and information regarding internal policy documents from governmental departments. The review will include fisheries legislation and policy, data ownership, data licencing, data storing, and Freedom of Information requests that have occurred within the context of fisheries data relating to IDV. Some of industry’s concerns regarding IDV relate to how the data will be used outside of a fisheries context, and we will ensure that our legislative review includes advice regarding data use. The review will provide information on Australian legislation relating to IDV, and data collection, storage and sharing. 4) Assessment of value-add opportunities Building upon the findings from (1-3), we will assess the value-add opportunities presented by adopting IDV. This assessment will include a financial model similar to the one in the report “Challenges, Opportunities, and Costs of Electronic Monitoring” that was published by The Environmental Defence Fund in 2016 [REF] that will provide industry with a tool to investigate the costs and benefits of adopting various IDV methods. Additionally, we will explore how IDV can contribute to improved market access, stakeholder relationships, and sustainability credentials for fisheries businesses, alongside the potential of improved data quality from fisheries. Our work will build on our planned literature and legal review of independent data validation (IDV) and provide potential ‘value-add’ opportunities for commercial fishers, based on the information in the review. Some potential benefits may include: • Increased or improved market access (where IDV can demonstrate aspects of sustainable fishing practices required by, for example, sustainability labels such as the Marine Stewardship Council Certification). • Potential for selling or distribution of data to researchers / third parties (depending on data owners.
We will include updated outcomes and outputs from the project as detailed below, and will look to refine these with the Professional Fishers Association of New South Wales, commercial fishers, and the Steering Committee.
5) Best Practice Guidelines We will provide industry and fisheries resource managers with a Best Practice Guideline relating to IDV as a formal result from the steps (1-4) above. 6) Engagement with Industry Stakeholders Throughout the project, we will actively engage with industry stakeholders through workshops, focus groups, and one-on-one consultations to discuss project findings. This engagement will provide a platform for dialogue, collaboration, and knowledge sharing, fostering a sense of ownership and commitment among stakeholders towards implementing IDV practices. We will facilitate target outreach efforts engaging with industry associations, peak bodies, government agencies, and non-governmental organizations (NGOs), and other interested parties on the project progress.
Objectives: 1. Deliver a systematic literature review of global independent data validation methods, and the costs and benefits associated with implementing these in commercial fisheries. 2. Deliver a report on industry opinions and concerns based on stakeholder consultation 3. Deliver a review of legislation and policy that is relevant. and relating to independent data validation methods in Australia 4. Provide opportunities for stakeholder engagement in the project, and in discussions regarding the outcomes. Read moreRead less
Objectives: 1. Evaluate small manned submersible as observation platform when underwater observation is desirable but depths preclude normal diving activity, 2. e.g. monitoring off-shore artificial reefs, fish aggregating devices, fishing gear, examination of bottom substrate
Aquafin CRC - SBT Aquaculture Subprogram: Risk And Response - Understanding The Tuna Farming Environment
Funder
Fisheries Research and Development Corporation
Funding Amount
$1,594,867.00
Summary
Representatives of the tuna industry have expressed a clear need to understand the oceanography of the Port Lincoln tuna farming region so that they could predict likely trajectories and effects of phytoplankton blooms and any instances of dirty water on tuna farming, enabling them to develop emergency management protocols for such events. They also need to identify the range of variation in environmental conditions in both the water column and sediments within the farming zone and how this mi ....Representatives of the tuna industry have expressed a clear need to understand the oceanography of the Port Lincoln tuna farming region so that they could predict likely trajectories and effects of phytoplankton blooms and any instances of dirty water on tuna farming, enabling them to develop emergency management protocols for such events. They also need to identify the range of variation in environmental conditions in both the water column and sediments within the farming zone and how this might impact on farming practices, particularly if fish are to be kept for longer periods and if stocking numbers increase. In the event of an emergency (e.g. algal bloom, oil spill, disease outbreak), the industry needs to identify areas likely to be impacted and safer areas where pontoons might be relocated. Industry would also benefit from real-time weather and oceanographic information being available at the farm site to optimize visits to the farms for feeding, maintenance etc.
To meet this need, we propose to develop an integrated hydrodynamic and biogeochemical model of the tuna farming area, based on that which CSIRO have developed for the Huon Estuary. Based on the knowledge that CSIRO have gained from this previous study, and our knowledge of the data available for the Port Lincoln area, a number of knowledge gaps have been identified that need to be addressed before we can have confidence in the outputs of any model that is developed. These gaps include the extent and nature of benthic-pelagic coupling in the area (ie how do nutrients move between the water column and the sediments), the nature and role of phytoplankton in the system, the nature of the hydrodynamic regime in the area, and how prone the sediments are to resuspension under different wind and wave regimes. While it will still be possible to develop a basic modeling framework without addressing these knowledge gaps, we feel that doing this will result in the development of a poorly calibrated and inadequately verified model that could provide misleading results, possibly resulting in decisions by farmers and managers that are detrimental to the industry.
The industry depends on a healthy marine environment to maintain production and profitability. Tuna farms are a significant point source of nutrients into the marine environment (most of the nitrogen in the feed is excreted as ammonia), but this needs to be put into the context of natural nutrient levels and their seasonal variations. It is important to establish the carrying capacity of the farming region which both maintains a healthy and productive industry and protects marine environmental values. Phytoplankton blooms, including potentially harmful species such as Chatonella, are known in the Port Lincoln area but the causative factors are poorly understood and the influence of advection from regions further off-shore (e.g. upwelling cells) is unknown. Thus the risk they pose to the industry is unknown, and needs to be assessed.
Sediments are a key site for regeneration of nutrients back into the water column, but their quantitative importance in nutrient recycling in the Port Lincoln area is presently poorly known. Also, sediments are resuspended by waves and tide presenting an additional threat to penned tuna through gill damage, reduced feeding and as a possible source of harmful algal species from released cysts. The consequences of sediment resuspension can be dramatic as seen in the high mortality associated with the April 1996 event when tuna were held in pens located in shallow water inside Boston Island. While this is less likely with current farming practices, it would still be wise to properly asses the threat of a repeat event. Alternatively, during milder resuspension events, organic wastes may be dispersed over a larger area, allowing them to be assimilated more rapidly. The dropping of the nets to the seafloor at the end of the farming season may also act to disperse wastes and increase their assimilation.
This combination of issues and risks constitutes a significant scientific challenge. While we must continue to guard against any major environmental changes due to eutrophication, it is clear that more subtle environmental effects (phytoplankton bloom frequency and composition, zooplankton and jellyfish swarms, sediment resuspension) may affect industry production and profitability. Equally, regulators need assurance that marine ecosystems will not undergo unacceptable environmental change as industry develops. Industry and managers not only require knowledge of environmental changes, but a capability to resolve and predict the environmental response to changes in the offshore ocean regime, changes in catchment loads, and effects of the industry itself. Advances in observation technologies, in scientific understanding, and in modelling capability, together make it possible for scientists to develop the knowledge, understanding and prediction needed to underpin both long-term planning and short-term operational decisions. The goal here is for the CRC to work with industry and managers to provide an environmental information and prediction system which allows industry and regulators to manage environmental risk. Objectives: 1. Characterisation of the main oceanographic features of the tuna grow-out region at Port Lincoln through field studies and calibration of the three dimensional hydrodynamic model previously developed for salmonid farming in Tasmania. 2. Identification and description of dynamics of phytoplankton and benthic microalgal species, the factors causing algal blooms and the role, if any, of nutrients released from tuna farming. 3. Integration of phytoplankton and nutrient data into a 3D biogeochemical model for the Port Lincoln farming area that will allow movement of blooms etc to be predicted. 4. Refine description of variations in sediment type and assimilative capacity for organic matter including an assessment of the role of microbial and faunal communities in carbon remineralisation and nutrient release. 5. Application of sediment models to identify likelihood of sediments being resuspended and identification of factors affecting this together with an assessment of their role in algal blooms. 6. Further development of the near real-time telemetered environmental observation system with web access. 7. To develop an integrated hydrodynamic and biogeochemical model of the Port Lincoln tuna farming area, that will assist managers and farmers to assess how external and internal disturbances are likely to move through the area, and thus allow them to make informed decisions on how to best mitigate the risks associated with any given disturbance, and to develop pre-prepared emergency management protocols for particular events. Read moreRead less