Swimming against the current Records and scholarly studies indicate that before the 1970s the brook masu salmon could be found in six tributaries feeding into the upstream portion of the Tachia River. Today, a brief twenty years later, ichthyologists have found that there are only about 2,000 of the fish left, and these only in a five-kilometer stretch of the Chichiawan Stream.
根據資料記載與學界調查，民國六十年代前，櫻花鉤吻鮭原本廣佈在大甲溪上遊六條主支流裡，短短二十幾載，魚類學者卻發現，除了七家灣溪五公里範圍內的兩千條，其他地方已見不到櫻花鉤吻鮭蹤影。