Kebiasaan Makan Ikan Tuna (Thunnus sp.) Terkait dengan Proses Penangkapan pada Rawai Tuna di Samudera Hindia

Abstract

Information about fish behavior can be used to improve the effectiveness and efficiency of tuna fishing. One of fish behaviors that can be learned is feeding habits. The objective of this study is to examine feeding time and organism that commonly eaten by tuna in the Indian Ocean at position between 120 - 140 S and 1150 - 1200 E. The analysis was performed by observing stomach content of tuna. There were 19 bigeye tuna (Thunnus obesus), 6 yellowfin tuna (Thunnus albacares), and 6 southern bluefin tuna (Thunnus maccoyii) samples to be analyzed. The calculation of stomach fullness index and index of preponderance showed that the optimum feeding time of three tuna species range from 01.00 pm to 08.00 pm of local time. The prey of tuna was snake mackerel (Gempylus serpens), squid (Loligo sp.) and pomfret (Taractichtys sp). Snake mackerel, pomfret and squid have a bright color therefore it might be tuna use the sense of sight to find their food.