Aerobic diving limits of immature Weddell seals

Abstract

1. Consistent with previous studies on adult seals, post-dive blood lactic acid (LA) concentrations in immature Weddell seals did not increase above resting levels after short voluntary dives (Fig. 1). 2. Following longer dives, peak blood LA values increased rapidly according to the duration of the dive (Fig. 1). 3. The peak post-dive blood LA concentration relative to dive duration demonstrate that there is a positive relationship between aerobic dive limit (ADL) and body size (Fig. 1 and 3). 4. The ADL for 130 to 145 kg seals was about 10 min, and it was 13 min for 185 to 205 kg seals (Fig. 1). 5. The calculation of the ADL from available oxygen stores correlates well with the lactate/endurance curve intercept, where peak post-dive LA concentration rises rapidly above resting levels as the dive duration increases in adult and immature animals (Table 2 and Fig. 3). 6. Of total dives, 4% of the dive durations exceeded the measured ADL in 130 to 145 kg seals and 8% in the 205 kg seal (Fig. 2). 7. Dive depths of immature seals did not exceed 315 m (Table 1).