Abstract: The present study analyzes the spatial-temporal variation in feeding intensity of bigeye tuna(Thunnus obesus)in the tropical eastern and central Pacific Ocean based on the data collected by tuna scientific observer on aboard Chinese tuna longliner operating in eastern Pacific Ocean from February to November in 2006 with supporting of China Tuna Fishery Observer Program.The results showed that the smaller bigeye tuna with fork length smaller than 140 cm had greater feeding intensity than the larger individuals did.The lower feeding intensity was observed from March to April and the higher feeding intensity occurred from May to November.Higher proportions of empty stomach were found in March,but the proportions of empty stomach are found below 15%from May to November.The bigeye tuna showed an active feeding at a depth of below 200 m to 350 m.There were significant differences in feeding intensity in various months(χ2=227.95,P＜0.0001),fork length classes(χ2=364.61,P＜0.0001)and water layers(χ2=178.50,P＜0.0001).
2011, Vol. 26 
