Energy savings in sea bass swimming in a school: measurements of tail beat frequency and oxygen consumption at different swimming speeds

Tail beat frequency of sea bass, Dicentrarchus labrax (L.) (23.5 +/- 0.5 cm, L-T), swimming at the Front of a school was significantly higher than when swimming at the rear, for all water velocities tested from 14.8 to 32 cm s(-1). The logarithm of oxygen consumption rate, and the tail beat frequency of solitary swimming sea bass (28.8 +/- 0.4 cm, L-T), were each correlated linearly with swimming speed, and also with one another. The tail beat frequency of individual fish was 9-14% lower when at the rear of a school than when at the front, corresponding to a 9-23% reduction in oxygen consumption rate. (C) 1998 The Fisheries society of the British Isles.