Body composition of harp seals

Rosemary Gales, Deane Renouf, and Elizabeth Noseworthy
Ocean Sciences Centre. Memorial University of Newfoundland. St. John 's, NF, Canada, A1C 5S7
Canadian Journal of Zoology. 72: 545 - 551
Abstract: Using chemical analysis we measured the composition of 26 harp seals (Phoca groenlandica) representing both sexes, aged between 3 months and 30 years, and encompassing a wide range of body conditions. Predictive relationships between total body water and total body fat contents, total body protein content, and gross energy were calculated. These equations allow accurate estimation of harp seal body composition provided total body water content and body mass are known. Using these data we compared the accuracy of three existing equations that have been used to predict body fat content of other species. We found that in adult harp seals, lean body mass has a relatively stable hydration of 70% but the hydration of blubber varied with body condition. Lipid content, and thus energy density of blubber, increased with increasing body condition.