Preliminary Results on the Exploration of Tuna Resources in the East Indian Ocean

Abstract

Tuna purse seine fishing operation of M.V. SEAFDEC in the East Indian Ocean has been carried out since 1994. Aggregating tuna by floating FADs (Fish Aggregating Devices) are used in the fishing groung. Tracking of the FAD drift route during each season of the year was recorded. It was found that, in the early months of the year (from February to March), FADs set above latitude 5°S drifted in northeasterly direction and some, after nearly reaching the equator, turned back toward the west whereas FADs set below latitude 05°S drifted in an eastly direction. In the latter period of the year (October-November), FADs drifted eastward and then turned to the southeast at about longitude 088°- 091° E. The track of FADs in 1997 was exceptionally unusual, all FADs set during the year drifted rapidly westward, which is possibly a consequence of the El Nino Effect. Main catch during the fishing operation were Skipjack tuna Katsuwonus pelamis(Linnaeus, 1758), Yellowfin tuna Thunnus albacores (Bonnaterre, 1788) and Bigeye tuna T. obesus (Lowe, 1839)