Abstract Maximum daily consumption (C max) by adult white crappies Pomoxis annularis (164–532 g live weight) provided ad libitum rations of prey fish was determined at 18, 21, 24 and 27°C. Observed increases in C max between 18 and 24°C followed by a sharp (two-thirds) decline at 27°C indicated that a low to negative physiological “scope for growth” exists for white crappies at 27°C and above. Examination of temperature and dissolved oxygen (DO) profiles from numerous Missouri impoundments for May–August 1991 suggested that white crappies were forced to occupy water of 27–32°C (warm water) in 40% of these impoundments by early June and 85% by early August. White crappies were forced into warm water in only a slightly lower percentage of the deep (>5 m) impoundments we examined than in shallow (≤5 m) ones. Evaluation of year-to-year differences (1988–1991) in time periods when white crappies were forced to occupy warm water in Lake Pomme de Terre, Missouri, showed that range (15–64 d) and time of occurrenc...