Mouth-breeder fish (Tilapia spp.), originally from Africa, introduced to Taiwan in the 1950s, have now taken up residence in almost all the island's rivers.
外來種封殺本土物種的事件多不勝數，來自非洲的吳郭魚在民國四○年代移民寶島，如今幾乎取得台灣所有河川的居留權。