Muscle temperature and swim velocity profiles during diving in a Weddell seal, Leptonychotes weddellii.

Locomotory muscle temperature and swim velocity profiles of an adult Weddell seal were recorded over a 21 h period. The highest temperatures occurred during a prolonged surface period (mean 37.3 degrees C, S.D. 0.16 degrees C). Muscle temperature averaged 36.8 and 36.6 degrees C (S.D. 0.25 degrees C, 0.19 degrees C) during two dive bouts and showed no consistent fluctuations between dive and interdive surface intervals. Swim velocities were also constant, near 1.3 m s-1. These data indicate that past records of low aortic temperatures (35 degrees C) during and after prolonged dives are not indicative of whole-body temperature changes, and that muscle temperature, even during dives as long as 45 min, remains near 37 degrees C.