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whales journey across the ocean, leaping, leaping and playing, with grace and speed that belies their sheer size. The secret of their incredible lifestyle, in addition to their well-adapted skeletal and muscular structure, is a very unique respiratory system specialized for deep-sea diving. Over the course of its evolution, this respiratory system has had to overcome the challenges of mammalian anatomy. Just like all the others mammal, whales need oxygen-rich air to survive. They have a series of large, complex lungs that constantly exchange fresh oxygen for carbon dioxide to stay alive. Because whales do not have gills, they cannot get oxygen directly from the water. This makes them vulnerable to suffocation if they don’t return to the surface in time. Fortunately, cetaceans have evolved several extreme adaptations to survive the long and arduous journey beneath the surface. Read on to find out how long whales can hold their breath for.
How does a whale breathe?
The most important feature of any cetacean respiratory system (be it the sperm whale, humpback whale, killer whale, etc.) is the blowhole at the top of the head. The blowhole remains closed by default to prevent water from entering the body. After returning to the surface, the whale opens its blowhole by contracting a small muscular flap; it then exhales stale air from its body in a towering gust of pressurized air. The water you see coming out of the blowhole is not coming out of the lungs. Instead, the exhalation from the blowhole is so powerful that it sends the surrounding water up from the surface of the body in a fine mist into the air.
Once the stale air is expelled from the body, the whale will take a series of rapid breaths to replenish its oxygen. Most species only surface for a few minutes before relaxing the muscles around the blowhole and then diving back below the surface. To keep the water out of their lungs when they eat, cetaceans generally don’t breathe through their mouths. However, scientists have discovered that some dolphins with damaged blowholes can learn to breathe through the mouth as a last resort.
How long can a whale hold its breath?
The answer to that question definitely depends on the species (and also on the individual). One of the most impressive of all cetacean divers is the sperm whale (the kind with a large rectangular head). It can hold its breath for about 90 minutes as it dives to depths of more than 3,000 feet to feast on a favorite meal, giant squid.
However, the sperm whale is not the only impressive whale diver. The blue withhale (the largest animal that ever existed) can hold its breath for up to 90 minutes and usually resurfaces after about 30 minutes; the deepest dive ever recorded by a blue whale was about 300 meters below the surface.
The humpback whale (the most obvious feature of which is the large hump on its back) can hold its breath for up to an hour at a time, but the typical foraging trip lasts about four to seven minutes on average. It rises to the surface, takes six to eight quick breaths, and then plunges back down. The deepest dive ever seen by a humpback whale was over 600 feet.
The killer whale, on the other hand, hunts a lot on the surface. This is reflected in his breathing capacity: he can only hold his breath for about 15 minutes on average. However, when prey is not as easy to find near the surface, the killer whale does have the ability to dive hundreds of meters below the surface in search of suitable prey. It will surface about every three to five minutes when traveling long distances.
peoplehave, in comparison, a much weaker breathing capacity. The average person can only hold their breath for a few minutes at a time. The longest human dive on record, with years of extensive training, was made in 2021 by Croatian diver Budimir Sobat. He held his breath for 24 minutes and 37 seconds.
What is the record for longest whale dive?
The Cuvier’s beaked whale, a deep-sea species that can grow up to 7 meters in length and weigh up to 6,800 kilograms, holds the record for the longest whale dive on record. This beaked whale can reach depths of nearly 10,000 feet and is constantly setting new (human-observed) records. In 2014, a tagged whale was thought to stay underwater for about 138 minutes before finally resurfacing. This record held for about six years until another whale was sighted in 2020 diving for more than three hours.
The Cuvier’s beaked whale is an interesting species for marine biologists to study. It is estimated that they spend about 90% of the time under the surface, perhaps more than any other mammal. This seems to push the boundaries of what whales can tolerate, and it’s not entirely clear why.
How does a whale hold its breath?
The secret of the whale’s breathing ability lies in the efficiency of the entire respiratory system. This starts from the moment of their first breath. While humans can only take in about five percent oxygen with each breath, whales can easily take in up to 90% oxygen, allowing them to derive more power with each breath.
Contrary to popular belief, whales do not have larger lungs (at least relative to their overall body size). Instead, they rely on several other incredible adaptations to survive deep underwater dives. For example, the volume of blood flowing through their veins flows on a massive scale: It’s perhaps three to four times the amount of blood compared to a similarly sized land mammal. Their blood also contains twice as much oxygen-carrying hemoglobin as other mammals. This means that their blood is particularly oxygenated to feed their hungry cells.
When whales dive into the water, their bodies will automatically divert blood flow to vital central organs such as the brain and muscles and away from any organs they are not currently using, including the kidneys and liver. With only the most vital organs working, whales can lower their heart rates to about four to eight beats per minute, just enough to stay alive. The blue whale is a particularly extreme example of this. It can apparently lower its
h
eart rate to about two beats per minute.
Finally, if all else fails and oxygen supplies run out, a whale can always switch to anaerobic respiration, which conserves precious oxygen but causes lactic acid to build up quickly, depleting muscles. This is normally a last resort; most whales have completed over 90% of their dive before ever switching to anaerobic respiration. A notable exception (again) is the Cuvier’s beaked whale. It can apparently remain submerged for at least an hour after anaerobic respiration has started without experiencing much visible muscle fatigue. This may indicate that there is something unusual going on in the beaked whale’s metabolism that scientists don’t yet understand.
A major problem that any deep-sea diver faces (be it a human, a whale, or something else) is tissue damage. Small pressure differences between gas-filled air cavities in the body (such as the lungs or inner ear) and the surrounding water can cause tissue to tear. This is usually known in scientific jargon as barotrauma. To withstand the pressure of a deep dive, some whales are believed to have extra veins lining the inside of these gas-filled cavities. When the whale reaches exceptional depths, the veins will then expand outward to fill the extra space in the cavity. At the same time, the lungs will collapse to prevent damage to them. Because so much oxygen flows through their blood, they don’t need to use their lungs again until they resurface.
How do whales sleep without choking?
Cetaceans generally have two different strategies for sleeping. They will either rest horizontally or vertically in the water, or they will sleep for a bit while swimming next to another person. Both methods involve states of sleep that are more similar to napping; much of their brain remains alert and active. Although breathing itself is an involuntary act, whales must remain sufficiently conscious to control the blowhole, as it requires voluntary muscle movements. This suggests that they don’t really sleep the way people do.
Can whales drown?
Whales don’t actually drown (as their lungs almost never fill with water), but they can suffocate from lack of oxygen. This can happen when a whale becomes entangled in a fishing net and panics and tries to dive deeper or gets stuck. Newborns may also have trouble reaching the surface. Sometimes they suffocate before breathing for the first time.
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