Respiratory Metabolism of Pumpkinseed (Lepomis gibbosus) in Relation to Swimming Speed

By use of a "tunnel" respirometer the relation between oxygen consumption (Y, mg O 2 /kg/hr) and swimming speed (X, body lengths/sec) for 45-g pumpkinseed at 20 °C was found to follow the equation log 10 Y = 1.65 4 + 0.31 X. Standard and active metabolic rates were 45 ± 6.6 and 408 ± 39 mg O 2 /kg/hr, respectively. Maximum 60-min sustained swimming speeds averaged 3.01 ± 0.27 lengths/sec.At low velocities, with more than one fish present, elevation of the metabolic rate occurred from aggressive behaviour, reaching one-half the active rate.