東海南區、臺灣海峽產白口魚之生殖生態的研究

Maturity and Fecundity of White Croaker, Argyrosomus argentatus (Houttuyn), in the East China Sea and the Taiwan Strait

曾萬年(Wann-Nian Tzeng) ； 劉錫江(Hsi-Chiang Liu)

《臺灣水產學會刊》 1卷2期 (1972/09) Pp. 20-30

https://doi.org/10.29822/JFST.197209.0004

摘要

本報告所採用之標本係1970年元月起至12月止，按月於基隆漁市場採集在東海南區，或臺灣海峽作業的雙拖漁船所漁獲之白口魚。以左葉卵巢之中段為卵徑測定及卵數計數之採卵部位。在卵徑組成中大型卵粒數隨着成熟度係數增大而增加；且各體長之魚，只要成熟度係數相近則卵徑組成也極其相似，故以成熟度係數為成熟度之指標。東海南區者之產卵期為六～七月，而臺灣海峽者較早為五～六月。最初成熟體長大致在160～169mm，相當於一歲魚之體長。兩區之性比皆不因體長而改變，但在產卵期較之其他時期性比有偏小的現象。孕卵數(Y)與體長(X，in mm)呈Ŷ=αX(上标 b)之關係，而東海南區者與臺灣海峽者並無顯著的差異，故兩區之本種魚的孕卵數與體長呈下式之關係：
Ŷ=2.167896X^(4.194400)•10^(-5)

並列摘要

Samples of white croaker, Argyrosomus argentatus (Houttuyn), were collected monthly from the catches of bull trawlers which operated in the southern area of the East China Sea and the Taiwan Strait from January to December 1970.
The maturity and spawning of the collected species were studied, and results are summarized as follows:
1. The maturity factor (The equation is abbreviated) is a reliable indicator of sexual maturity, because the percentage of large size ova in the ovary increases with the maturity factor, and the ovaries of the same maturity factor are similar in ova diameter size composition. (Fig.4)
2. The spawning season is from June to July in the East China Sea and from May to June in the Taiwan Strait.
3. The size at first maturity has been found to be 160 to 169 mm, corresponding to the size of one-year-old fish.
4. The sex ratio for all the specimens consistently about 1:1, although the male tend to predominate at the beginning of the spawning season.
5. The relationship between fecundity (Y) and total length (X) in mm is fitted by the allometric equation Y=αX(superscript b).There is no significant difference in the allometric equations of the East China Sea and the Taiwan Strait (Appendix Table 2), therefore, the relationship between fecundity and total length is calculated as follows:
Ŷ=2.167896X^(4.194400)•10^(-5)