Latency of food anticipatory activity (FAA) in greenback flounder Rhombosolea tapirina was about 21 days. Fish fed at meal sizes of 0.25 and 0.5%W day - 1 exhibited FAA under meal durations of 1, 3 and 7h. Fish fed at 1.5%W day - 1 showed FAA only at a meal duration of 1h. At each meal size, FAA was shorter and lower the longer the duration of the meal. The mean durations of FAA and post-feeding activity were correlated positively (r=0.87;P< 0.01;n=7). FAA persisted for <3 days during food deprivation. It is suggested that greenback flounder was capable of evaluating the energetic and temporal impacts of a single daily meal.