Browsing by Subject "squid resource"
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- ItemRestrictedA Bayesian analysis of the squid resource Loligo reynaudii(2012) Glazer, Jean Patricia; Butterworth, Doug SA Bayesian assessment of the squid resource was last performed in 2010. This paper presents results from an updated Bayesian assessment given that additional years’ data are now available.
- ItemOpen AccessPreliminary results from an updated assessment of the squid resource(2010) Glazer, Jean Patricia; Butterworth, Doug SA Bayesian analysis, to take full account of model uncertainty, was conducted in the past to assess the status of the squid resource Loligo reynaudii. The data included in the analysis comprised jig catches (1983-2002), trawl catches (1971-2002), jig CPUE (1985-2002), trawl CPUE (1978-1999), an autumn survey biomass index (1988-1997, 1999) and a spring survey biomass index (1987, 1990-1995, 2001). Twelve models, each assuming a discrete value for h (the steepness parameter in the stock-recruit relationship), ranging from 0.40 – 0.95 in units of 0.05, were run and results were integrated over these models. Subsequent to the presentation of the results from the above-mentioned analysis, additional data have become available and there have also been some modifications made to the input data. Time constraints have precluded conducting a complete reanalysis whereby the results are integrated over the 12 models that were previously considered, where each model assumed a discrete value for steepness h. This paper therefore compares results for the assessment model utilizing i) the previous data and ii) the updated data for one of the models considered, namely h=0.7. It is therefore important to note that the results presented here are a work in progress and will be subject to a fuller evaluation in the near future.
- ItemRestrictedResults obtained from projecting the squid resource, Loligo vulgaris reynaudii, 10 years into the future(2005) Glazer, Jean Patricia; Butterworth, Doug SA Bayesian analysis, to take full account of model uncertainty, was recently conducted to assess the status of the squid resource Loligo vulgaris reynaudii. The data included in the model comprised: • Jig catches (1983-2002) • Trawl catches (1971-2002) • Jig CPUE (1985-2002) • Trawl CPUE (1978-1999) • Autumn survey biomass indices (1988-1997, 1999) • Spring survey biomass indices (1987, 1990-1995, 2001) A detailed description of the biomass dynamic model is provided in Appendix A. Part of the assessment exercise included projecting 10 years into the future under various constant effort scenarios. The results from these projections are presented here.