The FRDC HDR has identified the lack of information on markets and price formation in Australian fisheries as a major research gap. The need for such analyses has also been discussed within the AFMA Economics working group, as such information was seen as essential in supporting fisheries management.
This project is an attempt to reduce this research gap. In doing so, the information produced will be of benefit to fisheries managers, fishers and the broader community as we move our fisheries closer to maximising net economic returns.
The focus of this study is on the markets relevant to the Southern and Eastern Scalefish and Shark Fishery (SESSF), which is the main supplier of fresh fish to the Sydney and Melbourne markets. To date, only very limited empirical research has been conducted for these fisheries in Australia [4-6], most of which is now fairly old and is unlikely to be valid for current market conditions. Since the early 2000s the seafood market in Australia has changed, for example, due to increasing seafood imports and increasing domestic aquaculture production. Hence, market dynamics for products supplied by domestic fisheries may have also altered.
This case study was identified by the FRDC HDR as of high importance due to the current challenges facing the fisher in terms of unfilled quotas. One potential contributing reason that quotas are not being taken is that to do so would result in lower prices; of potential benefit to consumers but not to producers. Instead, the lower catches may be supporting higher prices. The outcomes of this project can provide insights into the extent of to which the marker is contributing to quota undercatch.
The study will focus on the impact of changes in supply on the price received on the markets. While the potential response of fishers to these changes in price (including avoiding large catches) is also of relevance to fishery managers, this will require further bioeconomic modelling work that is beyond the scope of this study, but may be seen as a high priority for future research.
There is increased awareness of the need for ecosystem-based fisheries management, with increased public expectations for sustainable management of fished stocks. However, reduced catch levels and increasing costs have stimulated industry calls for reductions in management costs, or for more effective use of the existing cost-recovered funds. Budget limitations have already led to annual fishery independent surveys (FIS) carried out less frequently, reduced observer monitoring (ISMP) to fund other projects, alternation of FIS and ISMP from year to year, use of Crew Member Observers (CMOs) to collect on-board length frequencies, retaining species at lower tier assessments instead of Tier 1 assessments, ad-hoc implementation of more multiyear TACs combined with adhoc implementation of break-out rules, reduction of the frequency of Tier1 stock assessments, and the postponement of critical Tier 1 stock assessments. Whilst all of these approaches are feasible and practical responses, their combined influence on the effectiveness of the monitoring and assessment at achieving desired management objectives has not been tested or demonstrated.
Current budget restrictions on AFMA have resulted in a departure from scheduled monitoring and assessment work, with increasing ad-hoc decisions about which components of that work undertaken each year. There is growing concern by stakeholders that the present monitoring and assessment program is incapable of addressing these developments. SETFIA and other industry associations are particularly concerned that fishing concession levies funding current arrangements will become unaffordable.
Given AFMA's legislative objectives to ensure ecologically sustainable development, to maximise net economic returns and to ensure cost-effective fisheries management, AFMA has proposed this project to develop proposals for a structured and cost-effective research, monitoring and assessment program to respond to requirements and emerging issues in the SESSF over the next 5 years. It may be possible to extend this horizon should a fully quantitative project follow this proposal.
The fishery biology (reproduction, growth, age, gear selectivity, fishing mortality, etc.) of Western Australia's four most commercially-important shark stocks are relatively well understood. However, uncertainty regarding their migratory patterns remains a significant caveat to ensuring their sustainability and for the long-term viability of their target fisheries. Dusky and sandbar shark stocks are distinctly size-segregated. Juveniles are targeted by demersal gillnet and longline fishers off the lower-west and south-west coasts, hundreds of kilometres south of adults’ primary distribution. To maintain adequate recruitment to these stocks, shark fishing has been prohibited in the north-west to protect adult sharks. However, the extent to which adults remain vulnerable to capture during their southerly natal migrations cannot be ascertained due to lack of knowledge about those migrations. Gummy and whiskery shark movements between fishery management zones have significant implications for those stocks’ continued recovery from historical periods of overfishing. In particular, the effects of gillnet fishing in the south east of the State during the seasonal closure of the fisheries west of 118 degrees longitude and an apparent westwardly emigration of gummy sharks from the south-eastern management zone are of interest to fishery managers and industry alike. A unique opportunity to evaluate these and other spatial-temporal stock dynamics currently exists in WA via acoustic telemetry infrastructure deployed around the State through various projects. Data from the proposed research will provide a better understanding of the benefits and limitations of existing fishery management arrangements and a basis for developing spatially and temporally explicit stock assessment models.
South Australia contains 80% of the endemic Australian sea lion (ASL) population, where substantial fishing effort in the gillnet sector SESSF (~20,000 km net-lifts/year) and SA RLF (~1.5 million pot-lifts/year) increase the risk of fatal interactions.
A recent risk assessment (FRDC 2005/077) identified that subpopulations of ASL are highly vulnerable to even low-level bycatch from fisheries, with >40% of subpopulations at risk of extinction from as little as 1-2 additional female deaths/year over a 20-25 year period. The risk assessment identified that the current high proportion of depleted subpopulations of the species may be entirely due to sustained low-level bycatch by commercial fisheries.
ASL are listed as a threatened species under the Commonwealth EPBC Act, and a recovery plan has identified bycatch from bottom-set gillnet and rock lobster fisheries as the most significant anthropogenic contributor to the species’ lack of recovery. As such the development of measures to mitigate interactions with sea lions forms the most pressing ESD issues for these fisheries.
ESD assessments of both the gillnet sector of the SESSF and SARLF fisheries have identified interactions with seals as a significant issue. These assessments make at least seven recommendations to address protected species interactions (including seals), but little if any progress has been made to address these to date.
In order to have southern rock lobster taken from South Australian waters placed on the list of exempt native specimens for export under Part 13 and 13(A) of the EPBC Act, there is an imperative to address these ESD recommendations, as failure to do so may jeopardise current and future export exemptions.
Provisions of the Commonwealth Environment and Biodiversity Conservation Act, requiring strategic assessment of fisheries against the principles of ESD including the need to monitor, assess and, if necessary, mitigate the interactions of fisheries with protected species (Fletcher et al. 2002).
In both the SA rock lobster and southern shark fisheries, there are considerable, policy and research requirements relating to fishery interactions with fur seals and sea lions that need to be undertaken within the next 2-3 years in order to fulfil recommendations detailed in recent Bycatch Action Plans and ESD Assessments (detailed in B2).
The National Seal Action Plan requires the estimation of sea lion and fur seal bycatch in gillnet, trawl, trap, dropline and longline fisheries and quantification of interactions with fishing equipment.
Assessment for the need for fishery closures to protect sea lions in the Great Australian Bight Marine Park.
Pinnipeds are listed as protected species under the Commonwealth Environment and Biodiversity Conservation Act, and are known to interact with lobster and gillnet fisheries.
Methods for assessing, monitoring and mitigating the interactions of pinnipeds with lobster and gillnet fisheries are needed urgently.
This need is greatest in South Australia, where:
1. the majority of populations of Australian sea lions occur, and where declining populations have been identified, and where
2. Australia’s largest populations of New Zealand fur seals occur, and where
3. a valuable ($80 M) fishery for southern rock lobster (Jasus edwardsii) is located, and
4. where unquantified interactions between pinnipeds and the lobster and southern shark fisheries are known to occur.
The need to assess the interaction of the Australian sea lion with the South Australian lobster and southern shark fishery is particularly pressing, because the Australian sea lion:
(1) is Australia’s only endemic pinniped;
(2) may be more vulnerable to fishery-induced mortality than other species;
(3) is mainly confined to South Australia, with ~80% of pup production occurring in this state; and
(4) has recently been listed as Threatened (Vulnerable Category)under Commonwealth EPBC Act legislation.
Fletcher, W. J., Chesson, J., Sainsbury, K. J., Hundloe, T., Smith, A. D. M., and Whitworth, B. (2002). National ESD reporting Framework for Australian Fisheries: The “How to Guide for Wild Capture Fisheries” FRDC report 2000/145, Canberra, Australia.
This report provides the most comprehensive appraisal of the risk posed by bycatch to subpopulations of Australian sea lions and New Zealand fur seals, by the SA rock lobster and gillnet sector SESSF fisheries. Further it has identified the research required to ensure that SA rock lobster and the gillnet sector SESSF fisheries are managed according to ESD principles, and that interactions with seals are measured, assessed and mitigated. Adoption of these recommendations will lead to the development, and adoption by industry and management of mitigation options to reduce seal bycatch. This will ensure that outstanding ESD recommendations detailed in fishery ESD assessments and the mitigation of the key threatening process identified in the Australian sea lion Draft Recovery Plan are addressed, leading to the recovery and potential future delisting of the species.
Keywords: SA rock lobster fishery (SARLF), gillnet sector of the South Eastern Scalefish and Shark fishery (SESSF), Australian sea lion (ASL), New Zealand fur seal (NZFS), bycatch
Age composition data provides the key information necessary to effectively manage fisheries. The proposal provides a mechanism where age composition data can be gained using length frequency data and age composition data from different years and sampling events, which has previously been impossible. The benefits will be a reduced need for production ageing, more timely age composition data and the ability to construct age composition data from historical length frequency data where no samples were collected for ageing.
Currently the Age-Length Key (ALK) is the most widely used numerical method for assessing the age composition in a large sample of length-frequency data. However, the application of ageing data in this approach is restricted to the original sample of length distribution (ageing data from the same year the length-frequency sample is taken). Due to this severe limitation, the ageing information must be regenerated for each new data sample. Using the Fredholm First Kind equations, previous years ageing data can be used to generate the underlying age composition from the current length-frequency data. Furthermore, the ageing data may be added to include many years, improving the robustness of the statistic which can then be used to decompose the underlying age distribution from the given length frequency.
As noted by a number of referees, the major problem with the current methods is variable recruitment. We have demonstrated that the technique is tolerant to the most extreme changes in age frequency (see accompanying text). These extreme changes in age frequency are greater than any changes that could occur naturally through recruitment. The issue of variable growth may affect the efficacy of the approach, but to our knowledge, has only been observed in two species. These are black bream and blue grenadier. It is proposed that the technique be demonstrated on blue grenadier in the first year.
The cost of collecting ageing data is high, with approximately $150,000 spent each year on ageing samples from commercially important species within the South East Fishery. Due to the cost, the number of species aged is not optimal and species are prioritised on a scientific and social-political basis. The cost-benefit of applying this approach is intuitively a large reduction in cost of ageing to industry and more timely information on the age structure of the population. A formal cost benefit analyses will need to be conducted on a species by species basis. This is a function of different cost structures for ageing different species, different numbers of samples that need to aged for each species. These different numbers of estimates that need to be made for each species is primarily due to longevity and stock structuring.
The age-structured data obtained from this project will benefit the South East Trawl Fishery, the Great Australian Bight Trawl Fishery and the Gillnet, Hook and Trap Fishery which are supported by The Integrated Scientific Monitoring Program (ISMP) and various other stock assessment programs that rely on age-structured data.
Further, age composition data will be able to be reconstructed historically from species where samples were not aged but length-frequency data were collected. This will enable age-structured population analysis where the lack of ageing data prevented these stock assessment techniques from being previously used. The net effect of this approach is to greatly improve the knowledge base from which species are managed. One of key advantages of this approach is, if successful, will at the very least compliment current methods and provide temporal and spatial coverage of age composition information which is currently cost prohibitive and only collected for a few, high value species.
The implication of a technique that can provide age-composition data free from the restriction of those associated with the ALK is more cost-effective resource management.
The proposal has been developed in two parts, the first component is a 'Proof of Concept Study' where the use of the Fredholm First Kind Equations to provide age compositions from length frequency data will be further examined. If this is not assessed as successful in a workshop environment, the project will be terminated at the end of the first year. The second and third year will examine a broad range of species.
