A re-examination of underlying model assumptions and resulting abundance indices of the Fishery Independent Survey (FIS) in Australia’s SESSF
SESSF Monitoring and Assessment – Strategic Review
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.
Final report
Development of harvest strategies for selected SEF species
Given AFMA’s need to satisfy its ESD objective, there is a need to consider uncertainty explicitly and identify performance indicators and harvest strategies that are as robust as possible to incorrect assumptions and misinformed interpretations of data. Use of these indicators and harvest strategies will improve the chances of achieving a reasonable balance between the conflicting objectives of long-term resource sustainability and the maximisation of economic gains.
The project also addresses to some extent two key research areas in subprogram (B) of the Wild Stock Program of the SCFA Research Committee: “Biological and socio-economic evaluation of alternative management scenarios for different species and categories of fishery to provide a framework for management planning” and “The evaluation and provision of harvest strategy models through comparison of management strategies using theory and case studies, establishing objective performance indicators for different jurisdictions and identifying options which are appropriate to the nature of the fishery”.
FRDC project 98/102 has already identified several areas where there is considerable uncertainty. However, that project has focussed on ‘generic’ data-poor species (although tailored to some extent to the actual situation for jackass morwong, pink ling, tiger flathead and spotted warehou, species that have been identified as ‘high' and 'medium' priority by SEFAG). Ideally, harvest strategy calculations should be tailored to particular species to achieve optimal outcomes. This project will evaluate harvest strategies for the four species that received initial focus in FRDC 98/102. FRDC 98/102 also focused on situations in which the fishery is based on a single gear-type only. However, it is increasingly being realised within SEFAG that even within the trawl sector there are sub-fleets, each of which differ substantially in terms of their selectivity. For example, for blue warehou, the trawl fleet off New South Wales has a selectivity pattern closer to that of the non-trawl fleet based at Lakes Entrance than that of the trawl fleet based in Portland.
One of AFMAs legislative objectives relates to providing cost-effective management. Increasingly industry is being expected to bear some of the costs associated with the monitoring on which stock assessments and hence TACs are based. There is therefore a need for an objective process for determining the trade-off between monitoring costs and the ability to which AFMAs management objectives are satisfied. The aim of this study is to examine this question within the scope of the trade-off between catch and risk.
Finally, there is a major need for stock assessment on more species in the SEF. However, although data for many species is poor, there are nevertheless fewer assessments than there could be due to a lack of software for conducting the increasingly complicated assessments demanded by stakeholders. FRDC 98/102 has developed software modules for implementing several commonly applied stock assessment methods (including “Integrated Analysis” – the basis for the current assessments for blue grenadier, school whiting, eastern gemfish, and blue warehou). If the detailed output from the software that implements these assessment methods could be available in an easily useable and visual form, this software could provide a better basis for conducting routine stock assessments.