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SUMMARY: Bigeye tuna (Thunnus obesus) support a large commercial fishery in the Indian Ocean. However, explicit management strategies and harvest control rules are yet to be developed for the management of this fishery. We used a stochastic age-structured production model as an operating model to evaluate several potential management strategies under different assumptions of stock productivity. Five management strategies-constant fishing mortality, constant catch, quasi-constant catch, constant escapement, and status-dependent strategies-were evaluated and compared using the performance indicators including average catch, average spawning stock biomass, variation in catch, average fishing mortality and lowest biomass during the time period considered in the simulation. This study shows that (1) for the constant catch strategy, an annual catch of 90000 t would result in a low risk of stock being overfished while obtaining a stable catch; (2) for the constant fishing mortality strategy fishing mortality of 0.3 per year could yield a higher catch, but might have a high probability (64%) of stock dropping below the spawning stock biomass (SSB) that could achieve maximum sustainable yield (SSB msy ); and (3) for the quasi-constant catch strategy an annual catch of 110000 t was sustainable if the current SSB was higher than SSB msy. Constant escapement and status-dependent strategies were robust with respect to different levels of virgin recruitment and steepness. This study suggests that it is important to incorporate uncertainties associated with key life history, fisheries and management processes in evaluating management strategies.Keywords: Thunnus obesus, management strategy, harvest control rule, Monte Carlo simulation, Indian Ocean, age-structured production model. RESUMEN: Evaluación de las estrategias de gestión alternativas para el atún patudo, Thunnus obesus, en el océano Índico. -El patudo (Thunnus obesus) soporta una pesquería comercial importante en el Océano Índico. Sin embargo, las estrategias de gestión de reglas de control de las capturas / explícitos aún no se han desarrollado para la gestión de esta pesquería. Se utilizó un modelo estocástico de producción estructurado por edad como un modelo operativo para evaluar varias estrategias de gestión de potenciales bajo diferentes supuestos de productividad de las poblaciones. Se evaluaron cinco estrategias de gestión, la mortalidad por pesca de captura constante, constante, captura casi constante, escape constante, y las estrategias de estado-dependientes, y se compararon con los indicadores de desempeño que incluye la captura promedio, promedio de biomasa de la población reproductora, la variación en la captura, la mortalidad por pesca media, y la biomasa más bajo durante el período de tiempo considerado en la simulación. Este estudio muestra que (1) la estrategia de captura constante, una captura anual de 90 mil toneladas daría lugar a un bajo riesgo de sobreexplotación, mientras se obtiene una captura estable, (2) para la constante de la mortalidad ...

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