利用耳石探討台灣東部海域竹節鰆的年齡與成長

• Main Authors: 詹麗華, Jhan, Li-Hua
• Other Authors: 孫志陸, 臺灣大學:海洋研究所
• Format: Thesis
• Language: Chinese; English
• Published: 2009
• Subjects: 竹節鰆;絕對成長率;耳石;年齡查定;von Bertalanffy成長方程式; wahoo;absolute growth rate;otolith,;aging,;von Bertalanffy growth function; Labyrinth; golden redfish
• Online Access: http://ntur.lib.ntu.edu.tw/handle/246246/181246; http://ntur.lib.ntu.edu.tw/bitstream/246246/181246/1/ntu-98-R95241209-1.pdf

本研究利用耳石的橫斷切面作為年齡查定的形質，探討台灣東部海域竹節鰆之年齡與成長。自2006年1月至2008年12月間，在台東成功新港魚市場總共採集到436尾竹節鰆樣本，其體長(尾叉長FL)範圍介在47.5~138.7公分之間，體重(全重RW)範圍在0.6~21.5公斤之間。分析量測資料，得知竹節鰆的體長體重關係為RW=6.653×〖10〗^(-7)×〖FL〗^3.475。 研究結果顯示尾叉長在116公分以下的竹節鰆，可以判讀日週輪來鑑定其日齡；尾叉長在116公分以上，則因為靠近耳石邊緣其日輪難以判讀，需使用年輪來判定其年齡。尾叉長在116公分以下的竹節鰆樣本，判讀的日齡介在87~399天。以平均百分誤差(APE)及變異系數(CV)來評估其精確度，重覆判讀3次的結果，其APE值之平均為0.96%；CV值之平均為1.27%。而判讀的最大年輪為3輪，經校正後為3.7歲。以150天為分界，將所有判讀結果分別套適Gompertz 及von Bertlanffy方程式，估得成長參數分別為：L∞ = 74.47 cm，G = 15.126 yr-1，t0 = 0.182 yr以及L∞= 132.35 cm，K= 2.067 yr-1，t0 = 0.058 yr。日齡判讀結果顯示，絕對成長率(AGR, absolute growth rate)隨著日齡的增加而下降，前4個月的平均成長率為5.69 mm/day，顯示竹節鰆在幼齡時期成長快速。回推孵化日主要介在3到8月間，涵蓋台灣東部海域竹節鰆的產卵季節。 年輪的判讀在第一輪較不易驗證，因此本研究主要使用日齡來探討竹節鰆幼齡魚之成長，並確認切片耳石是竹節鰆日齡的最佳判讀工具，本研究補正前人研究高估竹節鰆幼魚成長的缺失，竹節鰆在1歲以下成長快速，且雌雄間成長速率並沒有顯著差異。 Age and growth of wahoo, Acanthocybium solandri, in the waters off eastern Taiwan were studied using the transverse sections of sagittal otoliths. A total of 436 fish ranging from 47.5 to 138.7 cm FL (fork length) and from 0.6 to 21.5 kg RW (round weight) were collected at Shinkang fish market during January 2006 to December 2008. The relationship between the round weights and fork lengths was RW=6.653×〖10〗^(-7)×〖FL〗^3.4745.esults indicated that daily increments could be read for fish smaller than 116 cm FL, while annual counts could be read for fish larger than 116 cm FL. The number of daily increments ranged from 87 to 399 days for the samples <116 cm FL. The ageing precision was 0.96% in terms of average percent error (APE) and 1.27% in terms of coefficient of variation (CV). The biggest annual counts for the sample fish >116 cm FL was 3 annuli which was adjusted to 3.7 years. All data were separated at 150 days into two groups for fitting two growth curves. The fitted Gompertz growth function for the smaller fish was L_t=74.47×e^((-e^(-15.126(t-0.182) ) ) ), and the fitted von Bertalanffy growth function for the larger was L_t=132.35×(1-e^(-2.067(t-0.058) )). Absolute growth rate (AGR) decreased with increasing age, and the average growth rate among the first four months was 5.69 mm/day indicating that wahoo grow very fast in their early life history. Back-calculated hatching dates span from March through August covering the whole spawning season of wahoo in the waters off eastern Taiwan. We acknowledge that identifying first annulus was much difficult. Thus in this study, we used daily increments to investigate the growth of wahoo at young age and proved that the transverse sections of otoliths were the best medium to age wahoo. This study makes up for the overestimation on the growth of young wahoo by previous researchers. Wahoo have rapid growth at their first year of life, and the growth rates do not differ between sexes. 目錄謝 I要 IIbstract III一章 前言 1.1 竹節鰆之外部形態與生態習性 1.2 漁業現況 2.3 耳石在漁業科學上之應用 3.4 前人研究 4.5 研究動機與目的 5二章 材料與方法 6.1 樣本採集 6.2 耳石製備 6.3 日輪與年輪的計數與驗證 8.3.1 日輪 8.3.2 年輪 8.4 資料分析 9.4.1 體長與體重之關係 9.4.2 耳石型質與魚體之關係 9.4.3 日齡判讀的精確度 10.4.4 成長方程式 11.4.5 回推孵化日期 12三章 結果 13.1 體長頻度 13.2 體長體重關係式 13.2.1 樣本體長與體重關係 14.2.2 耳石 14.3 耳石的構造 15.3.1 全耳石的外部型態 15.3.2 切片耳石的構造及判讀 15.4 資料分析 16.4.1 耳石的成長 16.4.2 耳石日輪判讀的精確度 17.4.3 成長方程式 17.4.4 回推孵化日期 18四章 討論 19.1 使用耳石探討竹節鰆日齡、年齡與成長之可行性 19.1.1 年輪 19.1.2 日齡 20.2 日齡的精確度 22.3 雌雄性比與其他海域不同之探討 23.4 年齡與成長之討論並與其他海域比較 23.4.1 體長範圍 23.4.2 探討成長速率的變動 24.4.3 成長方程式比較 26.5 回推孵化日期對照生殖生物學之研究 27.6 結語 28考文獻 29圖.35表.58amp;#8195;目錄ig. 1. Annual landings of wahoo, Acanthocybium solandri, in Shinkang fish market, 2002 to 2008. (Data source: Shinkang Fishermen’s Association) 35ig. 2. Measurement of fork length (FL) for wahoo, Acanthocybium solandri. 36ig. 3. Fishing grounds of the longline and troll fishing boats based at Shinkang fishing port. 37ig. 4. (a) Otolith removal with sagittal head section. A sagittal section is made passing through the middle of the cranial cavity. (b) Anatomy of vestibular apparatus. Position of the otoliths within the inner ear of teleost. (c) Otoliths with labyrinth systems of representative wahoo.(A = asteriscus, L = lapillus, S = sagitta, Lag = lagena vestibule, Sac = sacculus vestibule, Utr = utriculus vestibule). 38ig. 5. A transverse section on a sagittal otolith of wahoo, Acanthocybium solandri. 39ig. 6. The otolith radius (OR) of wahoo, Acanthocybium solandri, was measured from the core area to the furthest edge (postrostrum) of the otolith. 40ig. 7. Percentage composition by gear for the number of wahoo, Acanthocybium solandri, collected at Shingkang fish market from January 2006 to December 2008. 41ig. 8. Length frequency distribution by sex for the wahoo, Acanthocybium solandri, collected at Singkang fish market from January 2006 to December 2008. 42ig. 9. The relationship between fork length and round weight for the wahoo collected at Shinkang fish market from January 2006 to December 2008. 43ig. 10. The relationship between (a) otolith radius (OR) and fork length (FL), (b) otolith weight (OW) and round weight (RW), (c) otolith weight (OW) and otolith radius (OR) of wahoo, Acanthocybium solandri. 44ig. 11. (A) The three pairs of otoliths. (S = sulcus). (B) Otoliths from a 75.5cm FL (2 kg) male wahoo, Acanthocybium solandri, under 12.5X dissection microscope. The sagitta is usually the largest otolith and the one most often used for age determination. 45ig. 12. (a) Detail of the primary increments under transmission light microscopy. The incremental zone (translucent zone) contains more calcium carbonate than the discontinuous zone (opaque zone). (b) Detail of the core area under transmission light microscopy. (arrow sign = primary ring, triangle sign = primordium). (c) Using this check (about 225.08±3.92 μm S.D. from the core area) as the first ring while the sample had missing the data of core region. 46ig. 13. (a) Daily increments: Counting path of a transverse section of a wahoo sagittal otolith beginning at the primordium and ending near the post-rostral tip (b) Annuali: Dots indicate annuli counted on sectioned otolith. (AMD＝absolute marginal distance). 47ig. 14. A comparison of the edge analyses on sectioned wahoo otoliths between McBride et al. (2008) and this study. 48ig. 15. The relationship between (a) age (D) and otolith length (OL), (b) age (D) and otolith weight (OW) and (c) age (D) and fork length (FL) and of wahoo with sex combined. 49ig. 16. Relationships between average percent error (APE) of daily increment counts and (a) fork length (cm), (b) round weight (kg), and (c) Average counts (days) for 306 specimens of sectioned wahoo otolith. Horizontal line indicates mean APE for all samples. 50ig. 17. Relationships between coefficient of variation (CV) of daily increment counts and (a) fork length (cm) (b) round weight (kg) and (c) Average counts (days) for 306 specimens of sectioned wahoo otolith. Horizontal line indicates mean CV for all samples. 51ig. 18. The Gompertz (fitted for fish younger than 150 days) plus von Bertalanffy (fitted for fish older than 150 days) growth curve for the wahoo, Acanthocybium solandri, collected in the waters off eastern Taiwan during January 2006 to December 2008. 52ig. 19. Frequency distribution of the back-calculated hatching dates estimated from daily increments of wahoo younger than 399 days, which indicated the year around spawning season of wahoo with a peak from March to August. 53ig. 20. Detail of the core area after 5N HCl etching under transmission light microscopy. 54ig. 21. Growth curves of wahoo in the waters off eastern Taiwan using transverse sectioned otoliths (daily increments and annuli) during 2006-2008 (this study), in Florida and the Bahamas using transverse section otoliths (annuli) during 1997–2006 (McBride 2008), in Caribbean using whole otoliths (annuali) during 1998-1999 (Kishore and Chin 2001) and in North Carolina using whole otoliths (annuli) during 1964–1972 (Hogarth 1976). Data are restricted to collections from May to October by Hogarth (1976). 55ig. 22. Length at age of wahoo A. solandri, collected in the waters off eastern Taiwan during 2006-2008 (this study), North Carolina during 1964–1972 (Hogarth, 1976), Florida and the Bahamas during 1997–2006 (McBride et al., 2008) and Gulf of Mexico and Bahamas during 1997-1998 (Franks et al., 2000). Data are restricted to collections from May to October by Hogarth (1976), from May to September and November by Franks (2000). Vertical lines represent the length ranges. 56ig. 23. Relationships between absolute growth rate (AGR) and age (days) by sex. 57amp;#8195;目錄able 1. Summary of results of the otolith microstructure method applied to sagitta of wahoo. Observed the relationship between the AGR (absolute growth rate) and fork length by length groups, the growth rate decreased with increasing length in AGR value. 58able 2. The monthly number of specimens and ranges of fork length (FL) and round weight (RW) for the wahoo, Acanthocybium solandri, collected in this study. 59able 3. Numbers of female and male wahoo (A. solandri.) grouped by 5 cm intervals with chi-square values assuming a 1:1 sex ratio in each interval, and the chi-square values assuming a homogeneous sex ratio among intervals. 60able 4. Summary of the otolith microstructure methods applied to sagitta of wahoo. 61able 5. The Absolute growth rate (AGR) and Relative growth rate (RGR) of wahoo, Acanthocybium solandri, at size (in terms of daily increments) estimated in this study. 62able 6. Parameters of the Gompertz and von Bertalanffy growth functions by sex for A. solandri. There are no differences between the male and female in growth by using the Likelihood ratio test. And the AIC value of Gompertz is smaller than von Bertalanffy growth function that indicates the Gompertz function is great to describe the growth of wahoo in early life history. 63able 7. Comparison of the precision between different ageing methods by using otolith for bigeye tuna, Thunnus obesus, Atlantic blue marlin, Makaira nigricans, blackfin tuna, Thunnus atianticus, southern bluefin tuna, Thunnus maccoyii, narrow-barred Spanish mackerel, Scomberomorus commerson, Golden redfish, Sebastes marinus. 64