How much do large whales eat?

Estimates of the amount prey consumed by cetaceans have been used in ecological models and also directly compared to human fisheries yields. Most these estimates based on assumptions about energy requirements. However, lack direct measurements for large whales has necessitated extrapolation beyond data points available from smaller species. A number different parameterisations general regressions which requirements or consumption are estimated as proportional body mass raised some power B, were with Basal Metabolic Rate (BMR) widely Kleiber equation. The choice values a impact estimates, can differ an order magnitude, but modellers frequently forced make rather arbitrary decisions due data. Nevertheless, neither nor theory appear support B >0.75. Although parameter obtained status through common usage, not always actual need reflect this uncertainty. Comparison generalised relationships other sources, including rates filter feeding, oxygen seasonal changes stores, suggest upper bounds average daily metabolic rate whales. stomach contents indicated less than four times BMR formula, critically dependent digestion time there be little stored that migrate seasonally productive feeding areas either relatively low their size meet considerable proportion annual outside grounds.