農業部-水產試驗所全球資訊網農業部-水產試驗所全球資訊網

黑皮旗魚 (Makaira nigricans) 為臺灣東部海域重要經濟魚種，同時也是大洋性頂級掠食者之一。本研究探究黑皮旗魚在臺灣東部海域攝食生態，透過胃內容物組成分析，解析黑皮旗魚與臺灣東部黑潮生態系餌料生物相互關係。本研究採用相對性重要指數 (index of relative importance, IRI) 分析餌料生物種類對於黑皮旗魚攝食習性的重要性。研究結果顯示黑皮旗魚的胃內含物組成在不同體長之間存在顯著差異。大型黑皮旗魚運動能力強，可攝食游泳能力較強之大洋性魚類，小型黑皮旗魚則攝食活動力較小之餌料生物。黑皮旗魚在春季時，餌料生物以圓花鰹、飛魚為主 (IRI = 1,144、806)；夏季以白帶魚、頭足類為主 (IRI = 1,913、1,078)；秋季以圓鰺、鯖科為主 (IRI = 2,086、1,538)；冬季以頭足類、正鰹為主 (IRI = 1,465、828)，季節間有顯著差異。在體長組別間Class 1 (100–150 cm)，主要以頭足類、圓鰺為主 (IRI = 928、707)；Class 2 (151–200 cm)以頭足類、圓花鰹為主 (IRI = 867、623)；Class 3 (200 cm以上) 則是以頭足類、白帶魚為主 (IRI = 1,735、821)。本研究推測黑皮旗魚為機會攝食主義者，以大洋性表層各季節優勢物種為主要攝食對象。

As a top predator, the blue marlin (Makaira nigricans) plays an important ecological and economic role in pelagic ecosystems. The aim of this study was to explore the feeding ecology of blue marlin and the composition of their prey species off eastern Taiwan by examining their stomach contents. To understand the feeding habits of the blue marlin, we used the index of relative importance (IRI) to examine the prey composition. The results showed that the prey compositions in the stomachs of blue marlin were different among the differing size classes. The large blue marlin with high mobility preferred to feed on mesopelagic fishes, while the small blue marlin preferred to feed on small forage fishes. Otherwise, prey IRI values varied across the different seasons. The most common prey species in spring were Auxis rochei rochei and Exocoetidae (IRI = 1,144 and 806). The most important prey species in summer were Trichiuridae and Cephalopoda (IRI = 1,913 and 1,078). Carangidae and Scombridae were the major prey species in autumn (IRI = 2,087 and 1,538), while Cephalopoda and Katsuwonus pelamis were found most commonly in winter (IRI = 1,465 and 828). The results suggested that the blue marlin is an opportunistic feeder that feeds on the dominant pelagic fishes in each season.