| Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 97 === Lipspot moray, Gymnothorax chilospilus, is an abundant muraenid species and widely distributed in Taiwan. Little is known on the fundamental biology of moray eels. Therefore, the aim of this study is to investigate the reproductive biology of G. chilospilus in the eastern waters of Taiwan. A total of 648 specimens (including 497 males, 81 females and 70 sex-unknown) caught by bottom longline in the eastern waters of Taiwan were collected monthly from May 2006 to April 2007 at Hualien and Taitung , eastern Taiwan. The sex ratio is 14.3%. The spawning season was estimated to be from May to September (the peak of maturation was from June to August) based on macroscopical, histological examination of ovaries, oocyte diameter measurements and gonadosomatic index.
Otolith (sagitta) was used for age determination in this study. The monthly changes of the marginal increment ratio indicated that opaque zones on otolith were formed during October and January every year. The maximum numbers of opaque band were counted to be 7 and 8 for female and male, respectively. The growth rates of females and males were significantly different (P < 0.0001) by analysis of covariance. The size and age of minimum maturity of the female is 24.3 cm being 3 years old. The age and size of minimum maturity of the female is 22.4 cm being 4 years old. This inconsistent result revealed that the differences growth rate between individuals, maybe the possible reason cause for maturation. The relationship between body weight (BW) and total length (TL) was expressed as：BW = 0.0007 TL 3.1544（r2 = 0.8648, n = 551）. The parameters of the von Bertalanffy growth equation for this species obtained from nonlinear regressions were as follows: L∞=43.3cm TL, k=0.167/yr, t0= -2.2yr for male；and L∞=41.6cm TL, k=0.13/yr, t0= -3.18yr for female.
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