How Long Can Seals Hold Their Breath Underwater?

As aquatic mammals, seals have to be able to hold their breath for long periods of time while diving for food, seeking out mates, and fleeing from potential predators. But how long exactly can seals hold their breath while underwater? Which species of seal can hold its breath the longest? Read on to learn more; we’ll also cover some interesting facts you should know about these unusual and amazing animals!

How Long Can a Seal Hold Its Breath Underwater?

Depending on the species, seals can hold their breath underwater for anywhere from 15 minutes to two hours! There are 33 species of pinnipeds, collectively known as seals, within the taxonomic clade Pinnipedia. Three families fall under this group: the true or earless seals, eared seals or sea lions, and, strangely, the walrus, which is the only living member of the family Odobenidae. 

All species of seals are capable of holding their breath for long periods of time while underwater. Compared to us humans, most seals’ lungs are much larger in comparison to their body size. In general, the larger the seal, the higher their lung capacity, and the longer they can hold their breath. But even the smallest seal species, the ringed seal, is capable of holding its breath for up to around 45 minutes at a time.

Amazingly, many seal species’ lungs actually collapse while diving! This is intentional and meant to protect the seal from decompression sickness, also known as the bends. To save energy, their heart rates also slow considerably while underwater.

What Seal Species Can Hold Its Breath the Longest?

The largest seal species, the elephant seal, is the most skilled diver of all! While most other seal species can hold their breath for around 15 to 40 minutes, elephant seals can hold their breath for up to two hours while diving for food. It’s common for them to stay underwater for well over an hour at a time! 

Notably, elephant seals also dive deeper than any other seal species while hunting. They can dive to depths of up to 1,700 meters with ease. This is mainly thanks to their strong, muscular bodies and heavily reduced, modified limbs that are better suited for traversing water than land. 

Though they can look rather silly while flopping around along shorelines, elephant seals can swim at speeds of up to 10 miles per hour while diving. However, they tend to swim a bit slower than this to conserve energy when they aren’t hunting or mating. For a seal that can weigh over 5,000 pounds when fully grown, that’s pretty impressive!

Can Seals Sleep Underwater?

Seals are able to sleep while in water as well as on land. However, they usually don’t fully submerge themselves while sleeping. Most species are actually buoyant enough to sleep upright in a vertical, “standing” position. Alternatively, they may opt to lay horizontally and float that way, with their belly and head facing up.

While sleeping like this, the seal keeps its head just above the water to breathe oxygen as usual. Meanwhile, the rest of its body below its neck stays just under the water’s surface. Then, the seal simply floats along until it’s ready to wake up and resume hunting, mating, fleeing from predators, or socializing.

But some species of seals, like the harbor seal, are so well-adapted to underwater living, they are able to sleep for around 30 minutes at a time underwater! Since most seal species don’t sleep for long periods of time and rather take periodic naps in short intervals, this works out well for them.

More Amazing Facts About Seals

Want to know more about seals? Here are some incredible facts you might not know about them!

• The fastest species of seal is the California sea lion, which can reach speeds of up to 30 miles per hour while swimming!
• The world’s oldest seal was a female Baikal seal. Scientists at the Limnological Institute in Irkutsk, Russia, estimated she lived to be 56 years old.
• The largest species of seal, the elephant seal, uses its massive proboscis as a sort of amplifier for its loud, booming roars! It mainly uses its roaring call to attract mates.
• When in water, most seals will sleep with their brains “half awake” to stay semi-alert to the presence of predators. When they are on land, however, they are able to engage in a much deeper sleep.
• Seals are capable of a wide range of vocalizations, from barks to roars to growls and howls! Strangely, gray seals can even “sing” and mimic human speech.