Seasonal Changes in Energy Requirements of Harp Seals

Seasonal changes in energy intake of northwest Atlantic harp seals were modelled and implemented as a Microsoft Excel ™ spreadsheet. Energy intake of adults during the fourth quarter is almost double estimated intake during the second quarter, with intermediate values during the fi rst and third quarters. Reproduction increases female annual energy requirements by 18%, and adds 4% to the estimated population energy intake. The model was sensitive to changes in metabolizable energy, body mass, and the activity factors selected to estimate cost of activity. Changes in blubber conductivity and body composition had intermediate effects, while changes in water and air temperature and activity had little effect on model output. Comparing annual energy intake between a seasonally varying model