Please use this identifier to cite or link to this item:
Feeding habits of Trichiurus japonicus in the waters surrounding of Guei-Shan Island, northeastern Taiwan
|Authors: ||Hsu, Chien-Ming|
|Contributors: ||NTOU:Department of Environmental Biology and Fisheries Science|
Trichiurus japonicus;Stomach content;Stable isotope;Trophic position
|Issue Date: ||2020-07-02T07:40:33Z
|Abstract: ||帶魚為臺灣沿近海重要經濟性魚類之一，也是海洋生態系食物鏈之中、高營養位階的掠食者之一。故本研究於2018年3月至2019年2月期間，按月於宜蘭大溪漁港之櫻花蝦拖網漁船進行生物樣本採集，共計採集435尾，進行胃內容物組成與穩定同位素分析，探討在臺灣東北部龜山島海域日本帶魚的攝食習性與其營養位階。 樣本之肛前長介於37-390 mm，體重介於0.24-800 g之間，雌性樣本尾數為194尾，雄性樣本尾數為241尾，且透過胃內容物分析顯示，樣本整體空胃率為29.43%，小胃比率為54.94%，中胃比率為6.44%，滿胃比率為9.20%，隨著季節的更替，空胃率有逐漸下降的趨勢。主要攝食的物種以魚類、甲殼類為主，攝食主要以七星底燈魚(Benthosema pterotum)佔大多數(IRI為3718.82)、其次為燈籠魚科魚類(Myctophidae spp.)(IRI為566.96)、正櫻蝦(Sergia lucens)居第三(IRI為458.07)。在各體長區間與季節間所攝食的餌料生物組成有明顯差異，在攝食寬度上隨著體長的增加所攝食的餌料生物越少，在雌、雄之間所攝食的物種組成差異不大，在夏季、秋季；夏季、冬季；秋季、冬季兩兩季節間之攝食呈現高度重疊。在穩定同位素方面，穩定同位素碳值(δ13C)及氮值(δ15N)分別為-17.28‰(SD=0.69)及12.45‰(SD=0.57)；營養位階平均值為3.83(SD=0.17)，而在雌、雄之間的穩定同位素碳、氮值顯示有著相似的攝食習性且具有高度的攝食重疊現象，而在肛前長與穩定同位素氮值方面，有隨著體長的增加而上升的趨勢。本研究結果結果顯示日本帶魚對於食物種類的選擇性不高，會以環境中豐度較大或易掠食之物種為食。|
Trichiurus sp. is the one of the most important economic fish in Taiwan, and is also described as the middle and high class predators of the marine ecosystem food chain. The purpose of this study was to explore the feeding habits and trophic position of Trichiurus japonicus in the waters surrounding of Guei-Shan Island, northeastern Taiwan. Sampling was collected from Yilan Dasi fishing port to analyze stomach contents and stable isotope of Trichiurus japonicus to compare the prey composition using size class, sex and season (n=435) during March 2018 to Febuary 2019. Pre-anal length (PL) and body weight of the specimens ranged from 37 to 390 mm and 0.24 to 800 g were taken, respectively. The empty stomach, small stomach, middle stomach and full stomach ratios were 29.43%, 54.94%, 6.44% and 9.2%, respectively. %IRI showed that Benthosema pterotum (IRI=3718.82) was the most important prey for Trichiurus japonicus, followed by Myctophidae spp. (IRI=566.96) and Sergia lucens (IRI=458.07). There were significant difference observed in the feeding habit of different size group and season.The diet breadth became less complicated as the length increase. There was no significant difference between sexes. Overlapped prey composition were maximum between summer and fall, summer and winter, fall and winter. The mean stable isotope value of carbon (δ13C) and nitrogen (δ15N) were -17.28‰ (SD=0.69) and 12.45‰ (SD=0.57), respectively, and the mean trophic position was 3.83 (SD=0.17). The stable isotope value of nitrogen increased with the pre-anal length. Both the stable isotope of carbon and nitrogen showed similiar feeding habit and high overlap between the sexes. The result of stomach composition showed that Trichiurus sp. is not highly selective for prey items, mostly cosume the food mainly available in the waters surrounding of their habitats.
|Appears in Collections:||[環境生物與漁業科學學系] 博碩士論文|
All items in NTOUR are protected by copyright, with all rights reserved.