Dolphin and shark depredations on longline fishery from Nanfangao, northeastern Taiwan: assessment of catch damage and economic loss / 海豚及鯊魚咬食對南方澳延繩釣漁業影響之研究:漁獲及經濟損失之估計

碩士 / 國立臺灣海洋大學 / 海洋事務與資源管理研究所 / 96 / Total of 352 fishing operations of Nanfangao fishing vessels during February 2007 to April 2007 were recorded by the questionnaires. The catch damage rates by dolphins and sharks were 33.24% and 22.44%, respectively. The depredation rates in number and weight by dolphins were 10.20% and 9.52%, while those rates by sharks were 2.10% and 2.22%, respectively. Moreover, the depredation index by dolphins and sharks were 4.60 and 0.88. It also indicated that the dolphins preferred to bite dolphin fish, yellowfin tuna and bluefin tuna, however sharks preferred to bite dolphin fish, oil fish and billfsih. Based on the annual yields of Nanfangao longline fishery. The total depredation loss by dolphin and shark of Nanfangao longline fishery were respective NT 86,726,089 and NT 17,100,649 dollars, which occupied 9.08% and 1.79% of total income of Nanfangao longline fishery, respectively.

Identiferoai:union.ndltd.org:TW/096NTOU5274004
Date January 2008
CreatorsYa-Pin Liu, 劉亞萍
ContributorsKwang-Ming Liu, 劉光明
Source SetsNational Digital Library of Theses and Dissertations in Taiwan
Languagezh-TW
Detected LanguageEnglish
Type學位論文 ; thesis
Format81

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