A Bioeconomic Analysis of Yellowfin Tuna (Thunnus albacares) in the Western and Central Pacific Ocean

• Main Authors: San-Tai Hsu, 許三泰
• Other Authors: Shan-Non Chin
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/96786913615652987725

碩士 === 國立中山大學 === 經濟學研究所 === 104 === The purpose of this study is using Gordon-Schaefer and Gompertz-Fox surplus production models as the foundation to analyze and estimate biomass status on yellowfin tuna in the Western and Central Pacific Ocean. Japanese catch and effort data of Longline fishery and Purse Seine is used because most yellowfin tuna catches are from Japan. First step is to calculate the equilibrium of Maximum Sustainable Yield, Maximum Economic Yield, Open Access and Present Value Maximization in various discount rates and discuss relationships among them. Next step is to choose an appropriate model to analyze further. This study employs three different methods for analyzing including taxing, sensitivity analysis and prediction. Since predicting analysis is the most effective way among aforementioned three methods, we therefore use it to estimate biomass status on yellowfin tuna in the ocean. We find out that yellowfin tuna may be extinct around 2060 if we do not take any measure to sustain its biomass. Therefore, we need to limit both catches and efforts in order to recover decreasing biomass until reaching the equilibrium of Present Value Maximization.