2014-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/704874摘要：日本鰻為東亞重要的養殖魚種之一。然而，由於養鰻產業完全依賴天然鰻苗之供給，遂形成產業發展的瓶頸。近三十年來，日本鰻資源量有明顯下&#64009;的趨勢，東亞各國近年來遂興起了異種鰻的養殖風潮，其中以鱸鰻以及太平洋雙色鰻 (俗稱短鰭鰻) 在台灣發展最速。台灣本地共產出四種鰻苗 (日本鰻、鱸鰻、短鰭鰻、黃氏鰻)，掌握這些鰻苗的生物地理分布、資源現況以及來游機制，對於鰻魚資源管理與產業永續發展極有幫助。本計劃擬建構鰻苗來游六重因子假說，深入探討 (1) 新月假說、(2) 北赤道洋流分岔點變動、(3) 洋流與分支流變動、(4) 柳葉期長短、(5) 變態水溫、以及 (6) 河口溫度，對於鰻苗之輸送擴散、來游時間、以及來游量等之影響。本計劃四年的主要工作項目與目標為： 4年長期項目: 每月監測宜蘭鰻苗CPUE資料、收集東亞各地鰻苗樣本與鰻苗採捕資料、整理海洋氣候因子如ENSO指標、海平面表水溫、洋流與分支流動態等環境資料。 第一年: 比較日本鰻、鱸鰻、短鰭鰻、黃氏鰻鰻苗之溫度偏好與耐受性。測試鰻魚新月假說。 第二年: 分析與比較四種鰻苗柳葉期與變態期之耳石日周輪特徵。 第三年: 探討洋流變動與鰻苗CPUE之變化是否相關，分析鰻苗資源量變動可能之原因。 第四年: 探討台灣周邊海流與鰻苗輸送關係，建構鰻苗來游完整理論體系。 <br> Abstract: The Japanese eel (Anguilla japonica) is a commercially important aquaculture species in Taiwan. Because of the full dependence of the glass eel caught from the wild for aquaculture need, the available glass eel resource thus determines the sustainability of the eel aquaculture industry. In the past decades, glass eel abundances have been declining significantly. Therefore, the culture of other eel species becomes more and more popular during recent years in Taiwan. Abundant glass eels are imported from other countries, especially for the A. marmorata and A. bicolor pacifica. There are a total of 4 endemic eel species in Taiwan, namely A. japonica, A. marmorata, A. bicolor pacifica and A. haungi, understanding their biogeography, resource abundance and recruitment mechanism have great help for the resource management and sustainability of eel aquaculture industry. This project aims to construct the six factors hypothesis of the glass eel recruitment, analyzing the effect of (1) the new moon hypothesis; (2) NEC bifurcation; (3) oceanic current and its branch waters; (4) larval duration; (5) metamorphosing water temperature; and (6) estuary water temperature, on the dispersal, recruit timing and abundance of the 4 eel species. The main working flow of the project is: All four years: Monitoring glass eel CPUE data in Yilan twice a month, collecting glass eel samples and catch data of East Asia, processing marine environmental factors such as ENSO, SST and oceanic current dynamics. The first year: Comparing the water temperature tolerance of the 4 glass eels and testing new moon hypothesis. The second year: Using the patterns of otolith growth ring of the 4 glass eels to investigate the characteristics of otolith daily growth rings during larvae and metamorphosis stage. The third year: Analyzing the possible correlation of recruit abundance between eel species. The fourth year: Analyzing the linkage between oceanic conditions and glass eel recruitment.日本鰻鱸鰻太平洋雙色鰻黃氏鰻鰻苗來游