Summary: | 碩士 === 國立臺灣海洋大學 === 海洋資源管理研究所 === 95 === Abstract
The ocean sunfish ( Molidae ) is a cosmopolitan species. Only a few studies on ocean sunfish especially the fisheries biology have been done. The most common species of ocean sunfish caught by commercial fishery is the sharptail sunfish ( Masturus lanceolatus ) in the eastern waters off Taiwan. A total of 265 specimens (160 males, 105 females) were collected in I-lan and Hawlien from January 2003 to November 2006. The relationships between total length ( TL) and standard length (SL) were estimated to be TL=7.759+1.166SL (r2 = 0.980, n = 105, P < 0.05)for females, and TL=3.698+1.204SL(r2 = 0.971, n = 160, P < 0.05)for males. The relationships between body weight (BW) and standard length were expressed as : BW=9.98×10-4 SL 2.45 ( r2 = 0.987, n = 105, P < 0.05 ) for females, and BW = 3.33 х 10-4 SL2.68 ( r2 = 0.986, n = 160, P < 0.05 ) for males. The relationships between standard length (SL) and centrum radius were estimated to be SL = 3.383 R + 8.229(r2 = 0.962, n = 84, P < 0.05), and SL = 3.513 R - 0.243 (r2 = 0.847, n = 135, P < 0.05)for females and males, respectively. The growth band of vertebra centrum was found to form once per year, during March and April and up to 23 bands were counted. The von Bertalanffy growth parameters estimated based on 215 specimens were as followings: growth coefficient k=0.046 ( yr-1), asymptotic standard length L∞ =262.5 ( cm ) and t0 = -3.3489 ( yr ) for females; k = 0.0594 ( yr-1), L∞=231.0 ( cm ) and t0 = -1.852 ( yr ) for males. The asymptotic total weight was estimated to be W∞ = 838 (kg) for females and 702 ( kg ) for males .
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