Sensitivity analysis of catch-per-unit-effort of Atlantic bigeye tuna (Thunnus obesus) data series applied to production model

Abstract

Different datasets and a Bayesian production model were used to assess the status of the Atlantic bigeye tuna (Thunnus obesus) stock. Several datasets convey little information hence estimations of parameters are imprecise unless a very restrictive prior is used. Modes of posteriors calculated for composite datasets are in between modes of the posteriors calculated for separated datasets. Most of the calculations indicate that biomass has decreased until the beginning of 1990's when the stock was overfished. Catches decreased after 1999 but there is doubt if the stock was recovering in 2000's. The answer depends on the dataset and on the prior distribution.

Keywords

• evaluación de stock
• biomasa
• modelo de producción
• modelo bayesiano
• muestreo adaptable por importancia