• thermoregulation;
  • marine mammals;
  • body size;
  • exercise;
  • newborn marine mammal;
  • metabolic rate


A review of thermoregulation in marine mammals led to the following conclusions: very little is known about thermoregulation in large cetaceans. The only measured value for the metabolic rate of a whale, albeit a young one, was substantially higher than the predicted value for a terrestrial mammal of similar size. Very small and newborn marine mammals rely on a high metabolic heat production to sustain their body temperature during exposure to cold or in the water. The considerable insulation of some adult marine mammals may absolve them from the need for a high level of heat production. One marine mammal in tropical or subtropical waters is hypometabolic. There is evidence for a powerful control of thermoregulatory mechanisms by the anterior hypothalamic/preoptic region of the brain in two species. Thermoregulation in marine mammals during exercise remains paradoxical.