| 中文摘要 |
本計畫第一年除了回顧文獻以探討各種魚苗之最適放流地點及研擬建立魚苗放流之標準作業流程，也利用雷射燒蝕進樣系統的感應偶合電漿質譜儀(Laser-Ablation Inductively Coupled Plasma Mass Spectrometry, LA-ICPMS)分析黑鯛耳石上的微量化學元素比值，以分辨海中捕獲的魚是屬於放流魚種群或野生魚種群。第二年進行放流黑鯛和野生黑鯛的生殖生物學研究，以探討二者的潛在生殖能力間是否有差異。第三年探討如何提高魚苗放流之存活率。今年度為第二年計畫，探討放流魚種群潛在的生殖能力與野生魚種群的生殖能力間是否有所差異，包括 (一) 黑鯛雙重標誌放流海域的有標誌魚與無標誌魚樣本持續回收，及該批魚放流成效的持續評估。 (二) 放流再捕魚與海中捕獲的其他無標誌魚(主要為野生魚)，兩類魚群的生殖生物學分析樣本的製備完成。 (三) 放流再捕魚與海中捕獲的其他無標誌魚，兩類魚群的生殖生物學數據之差異比較完成。執行結果如下，已檢驗捕獲者146人次，總檢測漁獲1,642尾，其中有標誌魚76尾，總再捕率約為(76/108,000) ≒ 0.704?。標誌魚放流後在海中第一年體長約從放流時的5 cm成長至16 cm，體重約從2g成長至110 g，第二年體長約成長至19.7 cm，體重約成長至162 g，第三年體長成長至27.5 cm，體重成長至500 g。海中捕獲成熟雌魚卵徑為0.844 ± 0.054 mm，孕卵數在156,400與886,080之間，平均為443,648 ± 259,345粒。生殖腺指數(GSI)的估計，海中捕獲雌魚1-3月為8.68 ± 4.39、4-6月為2.30 ± 1.72、7-9月為6.29 ± 2.24。雄魚1-3月為4.30 ± 2.01，4-6月為2.27 ± 0.31、7-9月為 1.67 ± 1.08。肥滿度指數的估計，海中捕獲雌魚1-3月為18.64 ± 2.59、4-6月為9.20 ± 2.28、7-9月為 29.46 ± 6.93。雄魚1-3月為17.84 ± 0.44、4-6月為7.48 ± 2.37、7-9月為 27.99 ± 6.12。利用Petersen法估計資源量為2,304,489尾(95%CI = 2,050,000-2,558,000尾)，時間別殘存率介於0.40 - 0.72之間。Schnabel法的資源量估值為2,292,348尾(95%CI = 2,222,000-2,299,000尾)，時間別殘存率介於0.33 - 0.57之間。Petersen法的估值變方較Schnabel法高。放流貢獻度2006年10月為9.4%，累計至2007年9月為6.8%，累計至2008年10月為5.3%。據此結果可知，該批放流魚苗已在該海域至少存活三年的時間。 |
| 英文摘要 |
The purpose of this project in first year is to analyze the optimal release area of fry by reviewing literatures, to build the standard operating procedure of releasing program, and to analyze the main elements of otolishs for the specimens of black porgy from sea using Laser-Ablation Inductively Coupled Plasma Mass Spectrometry (LAICPMS) in order to discriminate where did they come from released stock or wild stock. The potential reproduction will be investigated of both released and wild individuals in second year. And how to enhance the survival rate of released fry for the release program will be done in third year. The aim of this year (the second year) includes (1) continuing to collect and study the recovering data, (2) preparing the reproductive data for both released and wild individuals, and (3) comparing the potential fecundities for both stocks. The results were as follows.
Till now, 76 marked individuals from the 1,642 catch were recovered and reported, recaptured rate was about 0.704?. The marked individuals grew up from 5 cm to 16 cm in length and from 2 g to 110 g in weight in 2006, to 19.7 cm and 162 g in 2007, and to 27.5cm and 500 g in 2008 after releasing. The diameter of egg was 0.844±0.054mm for the wild mature female. The fecundity of wild mature female was between 156,400 and 886,080 and its means was 443,648±259,345. The gonad-somatic index (GSI) was 8.68±4.39 and 4.30±2.01 in January-March, 2.30±1.72 and 2.27±0.31 in April-June, 6.29±2.24 and 1.67±1.08 in July-September for female and male fish, respectively. The Condition factor (CF) was 18.64±2.59 and 17.84±0.44 in January-March, 9.20±2.28 and 7.48±2.37 in April-June, and 29.46±6.93 and 27.99±6.12 in July-September for female and male fish, respectively. The stock size was estimated as 2,304,489(95%CI= 2,050,000-2,558,000) by Petersen method and 2,292,348(95%CI= 2,222,000-2,299,000) by Schnabel method. The survival rates were between 0.40 and 0.72 for Petersen method, and between 0.40 and 0.72 for Schnabel method. The accumulative stock contribution rate of released black porgy was about 9.4% in 2006, was about 6.8% in 2007 and was about 5.3% in 2008. The variance of stock estimates by Petersen method was higher than that by Schnabel method. This study concludes that the marked released individuals were survived for three years in sea area. |
