吳郭魚在臺灣（1946-1980）－外來種之適應問題探討

吳郭魚在1946年被引進臺灣，政府利用其易於養殖的特性，於1951年開始推廣稻田養魚，以供應軍民魚食；此舉不但擴大吳郭魚的養殖面積，增加魚產，同時也提高了農民對於養魚的興趣與認識。吳郭魚因為繁殖能力太強，導致池魚密度大增而影響其體型，不容易養成大魚，降低商品價值，因此養殖面積進展緩慢。1960年代臺灣水產界針對吳郭魚不耐寒與體型不大的缺點，不斷引進新的品種進行雜交試驗，希望利用雜交優勢，產生具備更耐寒、成長更快、抗病能力更佳等多重優點的魚種，以利業界生產。直至1968年改良成功的福壽魚受到漁民的歡迎，才改變情勢；此外，臺灣的吳郭魚養殖面積於1970年代擴張迅速亦與社會發展有關，此時農地改闢魚塭與農牧綜合經營政策，亦使得吳郭魚受到業界的喜愛。另一方面，吳郭魚順利地融合於臺灣，還需要考慮臺灣整體養殖產業的生態以及社會環境等因素，牠不但適合臺灣的魚塭生產體系，亦符合臺灣人的消費習慣，且在社會生活型態轉變的過程中，適時提供廣大外食人口廉價鮮魚的需求，凡此均使其成為臺灣重要養殖魚類；而近年來環境影響問題日益受到重視，引進吳郭魚之於生態的影響若何？亦為本文關注的課題。

關鍵字

吳郭魚；稻田養魚；水產養殖

並列摘要

Tilapia, also known as Wu-guo Fish, was introduced into Taiwan in 1946. A fast-growing tropical species. Tilapia did not become a valuable product in Taiwan immediately. It went through a long process of culturing and adjustment before being widely accepted by the local population. This essay explores this immigrant's survival story in Taiwan, especially from 1946 to 1980. To supply sufficient food to the populace and the military, the government began encouraging farming Tilapia in rice paddies in 1951. This policy appealed to farmers and expanded the farming area for Tilapia. The limited size of Tilapia lowered its prices on the market, and it was not a popular product at that time. Through non-stop hybridization, expert in Taiwan made cultured Tilapia bigger and stronger, and finally in 1968, cultured Tilapia became a true success. The new species was named Fu-sou Fish, suggesting its beneficial effects-longevity and happiness-on the consumers. As cultured Tilapia was more and more welcomed by the people, fanning it was increasingly profitable and the farming area expanded quickly from the 1970 onward. People even exchanged farmland for fish ponds in order to breed cultured Tilapia. Tilapia survived successfully in Taiwan not only due to its ability to grow well in ponds, but also to its appeal to people's taste for fresh and cheap fish. In addition, this essay investigates the ecological impact of cultured Tilapia on Taiwan' environment.