海豚群與非海豚群選擇上的兩難-以東太平洋熱帶區圍網漁業為例

外文標題: 
the dilemma of the choice between dolphin sets and non-dolphin sets-the case of the eastern tropical pacific purse-seine fishery
校院系所: 
國立中山大學 經濟學研究所
指導教授: 
曾憲郎
出版年份: 
2010年
主題類別: 
摘要: 

東太平洋熱帶區(ETP)圍網漁業作業方式可分為海豚群與非海豚群。海豚群捕到的黃鰭鮪較多,但有海豚混獲的問題;反之,非海豚群捕到的鰹鮪較多,但卻有鮪魚丟棄的問題。因此,漁民作業方式的選擇對ETP圍網漁業有很大影響性。若漁民多採用海豚群,則能捕抓到較多且較具經濟價值的黃鰭鮪,但卻會造成大量海豚死亡。反之,若漁民多採用非海豚群,雖不會傷害到海豚,但該作業方式捕到的鮪魚體型小,丟棄率相當高,這會影響到漁民整體的利潤。本研究想探討在同時面對海豚群會有海豚混獲與非海豚群會有鮪魚丟棄的兩難下,漁民該如何選擇作業方式。此外,管理者是否可以透過禁止海豚群或者禁止非海豚群,使漁民利潤極大,且又能維持鮪魚與海豚的生態平衡。

外文摘要: 

In the Eastern Tropical Pacific (ETP), the operation mode of purse-seine fishing can be divided into dolphin sets and non-dolphin sets. Dolphin sets can catch more yellowfin tuna, but cause a lot of dolphin deaths. On the contrary, non-dolphin sets can catch more skipjack tuna, but discard a lot of tuna. Therefore, the choice of the operation mode to the ETP purse-seine fishery is very influential. If the fishermen use more dolphin sets, they are able to catch high quantity and more valuable yellowfin tuna. Conversely, if the fishermen use more non-dolphin sets, they will not hurt dolphins. But the tuna fish caught by this operation mode is smaller in size and the discarding rate is extremely high which will affect the overall profits of the fishermen. The research will investigate how the fishermen make the choice of the operation mode in the dilemma between dolphin sets which cause dolphins-bycatch and non-dolphin sets which result in tuna-discarding, In addition, if managers can ban dolphin sets or non-dolphin sets to maximize the profit of the fishermen and maintain the ecological balance between tuna and dolphins.