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In Kingdom of Oceans: Fire and Ice viewers have the opportunity to examine the paradox of whales, penguins, iguanas and dolphins. These are all animal which inherited a burdensome legacy from their land-dwelling ancestors: they must breathe in open air. When an animal finds its food in the ocean waters, coming up for air can be a real inconvenience. The deeper a marine mammal has to dive for food, the longer it is going to need to be able to hold its breath to be successful. Humans who have trained can hold their breath underwater for around 20 minutes, but the average person can only hold his or her breath for 1 minute.
There are several adaptations that make it possible for marine mammals to stay submerged longer than a land-based mammal. For starters, they actually have more blood. For example, 12 percent of an elephant seal’s body weight is in blood, compared to just 7 percent in humans. They also have specialized chemistry allowing more efficient oxygen storage. Diving marine mammals have another surprising feature as well, collapsible rib-cages. As they dive to deeper depths, the rib-cage pushes in making the animal less buoyant. With these specialized features, the top diving marine mammals will probably always be the champions. Here are three amazing divers.
Fin Whale
The fin whale is the second largest creature on Earth, reaching maximum lengths of 82 feet (25 meters) for males and 89 feet (27 meters) for females. This whale inhabits all of the world’s major oceans, and in tropical to polar waters. Fins are baleen whales: They use the fringe-like baleen in their mouths to strain krill and tiny fish from the massive amounts of water they ingest as they feed. They are also masters at diving for a snack.
Maximum Depth: 350 Meters (1148 feet)
Can hold breath for: 20 Minutes
Weddell Seal
Weddell seals spend much of their time below the Antarctic ice, where the fish are plentiful and the predators are few. They have the southernmost range of any seal, but use the icy waters to their advantage. They have the ability to dive deep and hold their breath for an astounding length of time. All the same, they have to come up for air eventually. If natural openings are not available, no problem. Weddell seals use their teeth to open and maintain air holes in the ice pack.
Maximum Depth: 610 Meters (2000 feet)
Can hold breath for: 70 Minutes
Sperm Whales
As big as a bus, the winner of the deep diving competition is fins down, the sperm whale. The whale made famous in the novel Moby Dick has fascinated humans for centuries, especially because of their relationship to giant squid. Sperm whales and giant squid may even be mortal enemies. Many stories of deadly battles between these two massive animals exist, and sperm whales have even been seen with suction cup-shaped wounds and remnants of giant squid in their stomachs. Hunting for giant squid means diving deep though and the sperm whale has it down!
Maximum Depth: 1,000 + Meters (3,280 feet)
Can hold breath for: 90 Minutes
Tune in to Kingdom of the Oceans: Fire and Ice March 10 at 9 PM et/pt and again on March 21st at 10 PM et/pt if you missed it. Learn more about marine animals that breathe air and other amazing animals in this 4-part series. You’ll want to catch them all!
