By Susan Milius
By counting harbor porpoise breaths, researchers have come up with a new way to judge the animals’ hard-to-measure metabolism. The trick shows that the animals can burn energy more than twice as fast as humans.
Researchers analyzed the several thousand puff-huff respiratory sounds recorded per day from each of 13 harbor porpoises swimming freely in Danish waters. Including just everyday staying-alive body processes plus hunting and other activities, the animals’ average total energy use ranged from 7.8 to 31 megajoules per day, researchers report December 6 in the Journal of Experimental Biology.