臺灣博碩士論文加值系統

本研究的目的是針對高雄港附近海域及仁愛河中很常出現的鯔屬魚類大鱗
鯔與白鯔，進行鯔屬魚類的生殖生物學研究，以建立本土沿岸鯔屬魚類之
基礎生物學資料。標本的取得是每月定期以流刺網，在仁愛河、高雄第一
港口及西子灣沿岸用流刺網捕撈魚類。此外，部份標本收集自多位釣友於
仁愛河釣獲之鯔魚。標本先量測體長、體重，然後解剖判別雌雄，目測生
殖腺成熟度，進行生殖腺稱重並換算生殖腺指數（GSI=生殖腺重/體重
×100）及肥滿度指數 (CF=體重/尾叉長3×100)等工作，並取其中成熟度
較高之卵巢進行卵徑測量及卵數估算之用。此外，並將每月捕獲的新鮮魚
體10-15尾，進行生殖腺組織切片。高雄港附近海域的鯔屬魚類，其分佈
水域有所差異。大鱗鯔遍佈於仁愛河流域、高雄港內及西子灣海域，而白
鯔只分佈於西子灣海域。結果亦顯示大鱗鯔和白鯔的生殖期有明顯的差異
。大鱗鯔為每年十二月到翌年四月間，而白鯔則為終年產卵。雌雄性比方
面，兩種魚均明顯的不符合1:1的假設，大鱗鯔的雌雄性比為0.9:1，白鯔
則為2.2:1。由卵徑頻度分佈及組織切片所得的結果，判定大鱗鯔和白鯔
均為一次產卵的魚類。最初成熟個體，大鱗鯔和白鯔兩種魚的雌魚分別為
尾叉長14公分及11公分，而雄魚則分別為尾叉長13公分及11公分。孕卵數
則是大鱗鯔為5-10×104(尾叉長17.7 -24.2公分)，白鯔為6-20×104（尾
叉長14.5-18.5公分）。實驗結果雖無直接證據來證明這兩種鯔魚的產卵
場，但由大鱗鯔的卵徑頻度的分佈，顯示港外群的型量大於港內群，加上
四到六月間稚魚在港區內出現，推測大鱗鯔的產卵場是在高雄港外的附近
海域。至於白鯔則因未曾在港內捕獲，所以推測其產卵場是在港外離岸較
遠處。總體上來說高雄港附近海域產的白鯔與大鱗鯔，其產卵期、最初成
熟體長及孕卵數等生殖特徵均有顯著的差異。其中白鯔的孕卵數較多，最
初成熟體長較小，且為終年產卵等等生殖策略皆優於大鱗鯔，白鯔的族群
數量似乎會比大鱗鯔來的優勢，但是在此水域大鱗鯔的數量卻較白鯔優勢
。推究其原因可能與環境的水質條件有關。白鯔可能是對高雄港區內之水
質忍受度較差，所以儘管港區內食物較豐沛，白鯔仍然甚少進入河港區，
而僅限棲息在西子灣的沿岸海域，於是該族群的可利用資源便遜於大鱗鯔
。

This study investigated the reproductive biology of Chelon
fishes in Kaohsiung river and its harbor area. Fish samples
were collected monthly from various sources. Between Jan. 1992
to Mar. 1993, Chelon specimens were provided by anglers who
angled at Kaohsiung river. From Dec. 1993 to Jun. 1995, monthly
sampling were carried out by used gill net, at Kaohsiung river
and Harbor. Additional offshore samples were collected by beach
seine at the coast of Hsi-Tsu-Wan. The results shown that the
distribution of Chelon fishes were different. C. macrolepis was
distributed in both Kaohsiung river , harbor area and Hsi-Tsu-
Wan, C. subviridis was distributed restrictly in to Hsi-Tsu-
Wan. The reproductive periods of C. macrolepis and C.
subviridis were also significantly different. The former
spawned from Dec. to May, while the latter spawned all year
around. Sex ratio of C. macrolepis and C. subviridis were
female : male = 0.9 :1 and 2.2 : 1, respectively. According to
the frequency distribution of egg diameterand the examination
of gonad, it was confirmed that the C. macrolepis and C.
subviridis were group synchronous spawner. The size of females
were usually larger than males, the first maturing size of were
14 cm and 11 cm for female C. macrolepis and C. subviridis,
respectively and 13 cm and 11 cm for male. The fecundity of C.
macrolepis and C. subviridis were 4-10*104 and 6-20*104,
respectively. Several evidences show that the C. macrolepis and
C. subviridis have the seaward spawning migration. This is a
general reproductive characteristic of Chelon / Muglid fish
species. The reproductive characteristics of C. subviridis and
C. macrolepis were significantly different. The former was
better than the latter, but C. macrolepis dominated to the C.
subviridis.