Growth of juvenile pollack was assessed at five constant temperatures (9, 12, 15, 18 and 21 degrees C) in an 84-day trial. Duplicate groups of 75 fish (initial weight 143 +/- 2 g) were held in O-2 saturated water (102-103% saturation) and fed to apparent satiation. Growth increased as temperature increased from 9 degrees C up to a plateau at 12-15 degrees C (NS differences between 12 and 15 degrees C) followed by a decrease from 18 degrees C. No growth occurred at 21 degrees C. For the overall period, specific growth rates were 0.52% and 0.53% day(-1) at 12 and 15 degrees C compared to 0.40% day(-1) at 18 degrees C. Feed intake was maximum at 15-18 degrees C (0.68-0.69% day(-1)) and it was significantly lower at 21 degrees C (0.45% day(-1)). Apparent feed conversion ratio was significantly higher at 18 degrees C than at 12-15 degrees C (1.8 compared to 1.2-1.4). There was no significant change in fish whole body composition related to temperature. At the end of the experiment, fish growth recovery following a transfer from 18 and 21 degrees C to 15 degrees C was assessed using a 50-day challenge test. Growth rate of the previous 21 degrees C group was the same as in the 15 degrees C group (NS differences) and in the previous 18 degrees C group it was significantly lower. The study showed that pollack have a high capacity to recover from a prolonged period of low or no growth induced by high temperatures.