Burst swimming speeds of mackerel, <i>Scomber scombrus</i> L.

Abstract

Burst swimming speeds were measured in mackerel 0.275–0.380 m long by filming newly caught fish, first released into a large shore‐sited tank, using a high‐speed cine camera and real time TV camera. The highest speed was 5.50 m s −1 or 18 body length per second ( b.l . s −1 ) in a 0.305 m long mackerel at 12° C. The recorded maximum tail beat frequency of 18 Hz agrees well with 19 Hz predicted from the measured contraction time of 0.026 s for the anterior lateral swimming muscle. The stride length was close to 1 B.L.; the power, calculated from the drag, was 4.53 W, and, calculated from the muscle used, was 5.07 W; all suggesting that the mackerel is swimming close to its physiological limit.