Measured and corrected energy expenditure (EE in MJ), measured and corrected number or prey capture attempts (PrCA), energy gain (MJ) and foraging efficiency for female Antarctic fur seals during a foraging trip at sea, as well as mass at birth and at weaning for their respective pups (n = 14).

The corrected values of EE and PrCA (calculated as explained in Foraging efficiency section of Material and Methods) were used with the estimated energy content per average prey (EC prey in kJ) to calculate the energy animals gained while at sea (in MJ) and their foraging efficiency (i.e., the ratio of energy gain/EE). The measured pup mass at birth, the calculated mass at weaning (from individual Von Bertalanffy growth models), and the deviation of individual pup mass at 127 from the average sex-specific mass at weaning (9.74kg for females and 11.73kg for males) of pups from the tracked mothers are indicated in kg.