Deep-sea diving with emperor penguins
Emperor penguins are capable of diving to extreme depths—as deep as 1,500 feet. Usually, the penguins dive for 5 or 6 minutes at a time. However, emperors are able to hold their breath underwater for up to 22 minutes.
Instead of flying through the air like most birds, emperor penguins swim through the water. Emperor penguins use powerful strokes when swimming in the ocean.
“When they swim, they really are flying underwater," said Paul Ponganis, a research physiologist at the Scripps Institute of Oceanography in San Diego. "A penguin’s wings act the same while it’s swimming as a bird’s does while it’s flying."
Birds that fly through the air have hollow bones that allow them to remain light enough to fly in the sky. Emperor penguins, on the other hand, have bones that are solid. Solid bones make them heavier, so they can dive deeper in the ocean.
Surviving in the Ocean
Special feathers keep emperor penguins from freezing in the water. These feathers are tightly packed together—more so than any other bird. Oil covers their outer feathers and helps keep the ocean water from their skin.
In order to have enough breath underwater, emperor penguins must store oxygen. Special cells help their bodies store the oxygen necessary for these extreme dives.
When they dive, their heart rate slows, slowing the rate of their oxygen use. Still, the amount of oxygen in emperors’ lungs drops to a level that would make humans pass out, according to Ponganis.
Even after all this time holding their breath, emperor penguins make a grand exit from the ocean. They end their swims with a great leap from the water, landing on their bellies, and sliding on the ice.
March of the Penguins, the 2006 Academy Award winner for Best Documentary, will air on national television for the first time on the Hallmark Channel, Saturday, November 25.