Abstract
Using an energy components analysis of the 73 day continuous time-depth recording of a female northern elephant seal, we estimated the total daily energy requirement to be between 9.4 Mcal and 10.0 Mcal. Total prey energy consumed was estimated between 15.9 and 16.8 Mcal/day, yielding a diet of approximately 10.7 kg of mackerel or 21.0 kg of squid or hake per day. We estimate that at least 60 % of the dives must be successful to account for the mass gained during the period at sea.
