Decision analysis on the introduction of a new fishing fleet for skipjack tuna in the Southwest Atlantic

• Autor(a) principal: Andrade, Humber Agrelli
• Data de Publicação: 2007
• Outros Autores: Kinas, Paul Gerhard
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da FURG (RI FURG)
• Texto Completo: http://repositorio.furg.br/handle/1/922
• topic: Uuncertainty; Posterior probability; Skipjack tuna; Adaptive importance sampling; Bayesian analysis; Incerteza; Probabilidade a posteriori; Bonito-listrado; Amostragem adaptativa ponderada; Análise bayesiana

Usually fishery managers do not have complete information on the questions they are supposed to evaluate, hence they have to make decisions taking risks because of the underlying uncertainty. We used decision theory and a bayesian version of a biomass dynamic model to assess the problem of introducing a new purse-seine fleet in the skipjack tuna (Katsuwonus pelamis) fishery of the southwest Atlantic ocean (SWAO). Adaptive importance sampling (AIS) followed by the sampling importance resampling (SIR) were used to build and explore the posterior distributions. Because skipjack of the SWAO has been under-exploited increasing the catches by introducing purse-seine boats probably will not reduce too much the biomass. However the endorsement of purse-seine fishing days results in large economic risks for the traditional bait-boat fleet.