|Abstract: ||南方黑鮪保育委員會(CCSBT) 為制訂一套明確且透明之全球總可捕獲量(TAC)訂定機制，自2000年5月召開管理策略工作小組以來，即積極發展管理程序(MP)，並預訂於2004年第十一屆年會完成並確定MP。台灣已於2002年8月30日正式加入成為CCSBT延伸委員會和延伸科學委員會之會員，而CCSBT所發展之管理程序，將影響未來全球南方黑鮪(SBT)總可捕獲量之訂定，並進而影響台灣未來之漁獲配額。 本文分析日本自台灣進口南方黑鮪之價格波動，並問卷調查台灣南方黑鮪漁船之全年作業成本，以估算台灣參與捕撈南方黑鮪漁船之全年作業成本暨在每年6-10月漁季期間之成本。此外，並針對CCSBT於2004年4月「第三屆管理程序工作小組」會議所選出FXR_01、HK5_01、D&M_03及TAI_03等四套決策原則，探討在不同資源回復的管理目標下，對於未來TAC變化之模擬結果，以分析評估各決策原則對台灣南方黑鮪漁業之影響。 本研究發現台灣2002年南方黑鮪漁獲量雖只佔印度洋總漁獲量之1.07％，惟就SBT季節性專業船而言，平均每船南方黑鮪漁獲收益約可支應其全年平均作業成本之12.5％，倘就6-10月台灣南方黑鮪漁季期間而言，約可支應36.88%之作業成本。另，2003年台灣南方黑鮪作業船數約佔印度洋總作業船數之33.7％，是故南方黑鮪作業漁場具有紓解印度洋區其他作業漁場壓力之作用，因此，維持台灣現有南方黑鮪漁獲配額對印度洋作業漁船之整體營運相當重要。 按CCSBT在第三屆管理程序工作小組會議所採基本參考案例之模擬結果，倘將資源回復的管理目標訂為2022年產卵母族群的資源量為2002年之1.1倍水準，則業者在未來9年將面臨TAC必須大幅減少31.59% 至 49.70%之衝擊，惟倘將資源回復的管理目標訂為0.9，則TAC在未來9年之調降幅度將可減少至11.47％以內，且資源量亦可於2032年達到2002年之1.1倍水準，由此顯示，倘MP將導致短期TAC大幅調降，並讓業者預期在20年後TAC將大幅增加，則未來又將產生過度投資之問題，並不合理；為顧及產業之穩定經營，對於四套決策原則之選擇，建議採短期TAC波動幅度較小之D&M_03和TAI_03。|
For the purpose of establishing a transparent mechanism for deciding the global Total Allowable Catch (TAC) of Southern Bluefin Tuna (SBT), the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) has constructively developed the Management Procedure (MP) to manage the global TAC since 2000 started in the Management Strategy Workshop in May, 2000. According to the timetable, MP will be finalized and decided at the Extended Commission of the eleventh annual meeting of CCSBT in October, 2004. Since Taiwan has become a member of the Extended Commission and the Extended Scientific Committee of CCSBT since 2002, the implementation of MP will impact on Taiwan’s quota directly. This study analyzes the SBT import market in Japan to show the fluctuation of imported price from Taiwan and conducts a survey to estimate the operation cost of SBT fishing fleets in Taiwan annually and during the SBT fishing season from June to October. Based on the official report of the Third Meeting of the Management Procedure Workshop (MPWS3) of CCSBT, which was held in April, 2004, four candidate decision rules, FXR_01, HK5_01, D&M_03 and TAI_03, was selected. This study tries to evaluate their performances through the TAC projection on various stock-rebuilding tuning levels and to analyze their impact on the operation of SBT fishery in Taiwan. This study shows that, in 2002, although the SBT harvest accounts for only 1.07% of the total harvest of Taiwanese tuna longliners in Indian Ocean, the average revenue of SBT harvest for seasonal target SBT fleet can cover about 12.5% of their annual operating cost and about 36.88% of their operating cost during the fishing season started from June to October. Since the number of fishing vessels caught SBT accounts for 33.7% of the total number of fishing vessels in Indian Ocean of Taiwan in 2003, it is worth to know that the availability of SBT quota would promise the Taiwanese fishing fleets enough incentive to fish for SBT during June to October. In order to mitigate the fishing pressure of other fishing ground in Indian Ocean, it is important to maintain the current quota of SBT for Taiwan. According to the results on the performance of the reference case proposed by CCSBT during MPWS3, if the rebuilding tuning level for the SBT stock will be achieved in 2022 is set as 1.1 times of the SBT stock in 2002, the industries will face a dramatic decrease of TAC for 31.59% to 49.70% in the following 9 years. If the tuning level target is set for 0.9 times of the stock in 2022, the industries will face a minor decrease of TAC for 11.47％ in the following 9 years and the stock in 2032 would eventually be rebuild to 1.1 of the stock in 2002. It shows that it is unreasonable that if the MP would lead to a dramatic TAC reduction in the short run and to make the industry expect a dramatic TAC increase 20 years later, then the industry would over-invest again in the future. Taking into account of economic stability of the industry, a suggestion was proposed regarding how to choose the best decision rules from the four candidate decision rules. Both decision rules, D&M_03 and TAI_03, are therefore recommended to choose to show the ability to reduce the TAC fluctuation in the short run.