碩士 / 國立臺灣海洋大學 / 環境生物與漁業科學學系 / 101 / Snyder's gaper(Champsodon snyderi)is a species of Champsodontidae in the order Perciformes. It is one of the demersal fish caught incidentally by small scale trawl fishery in the coastal waters off Taiwan. In order to realize the reproductive features of this species, a total of 1246 specimens(674 female and 572 males)caught by otter trawl were sampled monthly between Oct. 2011 and Oct. 2012 in Dasi fishing port, Yilan county. The mean sex ratio was 0.54. The sex ratio had no significantly difference between sexs based on Chi-square test. The relationship between body weight(BW; in g)and total length(TL; in mm)showed that the C. snyderi had nosignificant difference between females BW=4.01×10-6 × TL3.15（n＝674, p&;lt;0.05）and males BW=6.39×10-6×TL3.02（n＝572 ,p&;lt;0.05）. The oocyte development could be divided into Chromatin-nucleolus stage, Peri-nucleolus stage, Yolk vesicle stage, pre-yolk stage, pos-yolk stage, Migratory nucleus stage , Reproduction stage，and Atretic oocytes stage by the histological examination and ovarian development measurements. C. snyderi is an asynchronous and a batch fertility spawner based on the following five techniques：macroscopic appearance of ovarian satge. Histological examination of ovaries, oocyte diameter measurement, GSI, and monthly percentage in each maturity stage. The spawning season of C. snyderi in the coastal waters of Taiwan was estimated all round year. With a peak occurred between Jan and Mar . The mean fecundity of this species is 298.20 ± 180.90 eggs.Length at maturity was estimated to be 58 mm TL and 62.4 mm TL for females and males, respectively based on relationship between proportion of maturity and total length.
| Identifer | oai:union.ndltd.org:TW/101NTOU5451019 |
| Date | January 2013 |
| Creators | Guo-Yuan Chen, 陳國源 |
| Contributors | Shoou-Jeng Joung, 莊守正 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 65 |
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