臺灣地區日本鰻苗之資源管理

Abstract

日本鰻 (Anguilla japonica) 是亞洲水產養殖的重要魚種，而商業化之人工繁殖技術尚未建立，因此大量鰻苗在河口被捕撈以供養殖所需，造成嚴重的過漁問題，東亞各國已出現對日本鰻鰻線的爭奪戰，如何掌握與管理日本鰻鰻線的資源，為臺灣鰻魚產業永續發展的關鍵。本研究擬進行臺灣地區歷年鰻苗資源捕撈量調查，掌握臺灣地區鰻苗資源。另一方面進行臺灣地區鰻苗捕撈管理策略研究。結果顯示，漁業年報與業界所提供之鰻苗產量數據有顯著差異。由臺灣歷年捕撈量分析發現，台灣採捕年間波動大。由漁業年報資料顯示，臺灣產苗之月份為10月至4月，產苗地區為全臺靠海之縣市。由漁業署鰻苗通報系統可知，臺灣鰻苗產量之即時資訊，是臺灣急需建立之系統，但在鰻苗產量資料收集方式有待改善，建議納入全臺灣可捕撈到日本鰻苗之縣市漁會，以掌握即時與詳實之鰻苗產量。在管理策略研究方面，整理各國之鰻魚相關法規: 日本方面之法規以各道府縣為單位擬定相關規範；中國方面是以省為單位，訂立相關管理措施之細節；而韓國則是由中央統一規定；歐洲則是以歐盟為主，各國擬定；美國對鰻苗的規定則是由各州為單位。目前臺灣在每年11月1日至翌年3月31日禁止出口鰻苗，但因臺灣產之早期苗深受日本養殖業者喜愛，導致早期苗價高，故走私至日本情形嚴重，執法效果不彰。故為保護鰻魚資源與本地養殖業者，建議臺灣可以各縣市漁會為主體，施行鰻苗捕撈相關之證照制度，詳實記錄鰻魚苗捕撈量，並訂立捕撈時期為11月1日至隔年2月底。在管制日本鰻苗相關輸出規範方面，建議政府可派相關官員去與日本政府協商，希望可以臺灣禁止鰻苗出口的禁令，換得日本政府同意提前 (2月~3月) 出口日本鰻苗，達成中日雙方的雙贏局面。最後，建議政府可派官員積極和東亞各國協商，以求得鰻魚苗產業的最大利益。

Japanese eel (Anguilla japonica) is an important aquaculture species in East Asia. Due to unavailable commercial production of artificially propagated glass eels, the abundant elvers are caught on the estuaries to supply the aquaculture demand, which causes serious overfishing and competition among East Asia countries for glass eel resources. Therefore, monitoring and managing the eel resources should be the key strategy for the sustainability of eel aquaculture industry. In this study, we had investigated and monitored the yearly glass eel resource of Taiwan. We tried to establish a reasonable managing strategy of glass eels in Taiwan. Results showed that regarding the recruitment of Taiwanese elver, there is a significant difference in statistics between the Taiwan Fisheries Yearbook and Japanese aquaculture news. The annual glass eel recruitment is highly fluctuated. The Taiwan Fisheries Yearbook shows that the recruitment is between October and April, and in Taiwan the catching area is the countries near the sea. The Elver Online Reporting System discerns the elver production information and establishes online reporting system of elver fishing in Taiwan on time. However, the data collection method should be improved to reflect the actual situation. The suggestion for the improvement of the Elver Online Reporting System is to monitor the correct glass eel recruitment timely with the participation of all counties where elvers are caught. For management and strategic studies, we have collected relevant laws and regulation of eel management from Japan, China, Korea, Europe, Taiwan and the United States of America. The regulation for glass eel catch is based on units of county in Japan, province in China, central government in Korea, European Union in Europe, and states in U.S.A. In Taiwan, glass eels export is banned in period between November and March. However, the early recruitment of glass eels is popular for eel farmers in Japan, leading to a high unit price and illegal export by Taiwanese local eel traders. This indicates the ineffective enforcement of the law in Taiwan. The government should promote the fisheries association of counties all over Taiwan to form managing units, in order to perform regulations of glass eels to maximize the profit of fishermen and eel farmers and protect the eel resource efficiently. For example: 1. catch license must be applied so that the government can track glass eel recruitment. 2. The illegal catch time can be set between November and February. 3. The Taiwan officials are recommended to start to talk with Japanese government. If Japan agrees to export glass eel to Taiwan prior to Feb or March, Taiwan will cancel the ban on export elvers. This result surely will be favored by both sides. Lastly, the Taiwan government is suggested to consult with other East Asian countries to maximize the benefit of the eel industry.