Whales are marine mammals, and like all mammals, they require air to breathe and must come to the surface of the water to take in oxygen.
In these video, a pair of whales come by a boat for pets and head rubs, even rolling around.
Unlike fish, these marine mammals are not equipped with gills, which fish and other aquatic animals use to extract oxygen from water; Instead whales need to rise to the surface of the water to inhale oxygen and exhale carbon dioxide, through their blowholes.
When it comes to anatomy, all species of whale are broken down into two suborders based on their physical features.
These two suborders are known as the “toothed whale” and “baleen whale” suborders.
Baleen whales have large baleen plates in their mouths to strain tiny zooplankton from the water column, have two blowholes to breathe through, and are the larger of the two suborders. Toothed whales, which are smaller in size, and have conical teeth are born with a single blowhole.
In order to make it easier to breath, the whales blowhole(s) are located at the top of the whales head and act as a passageway to the trachea where air passes through the air passage and fills the lungs.
Having their blowhole on the top of their head makes it easier for them to breathe with minimal effort, especially during times of rest when they can be seen floating around, near, or at the surface of the water. This resting time is called “logging.”
While whales are known to breathe through their blowholes, they are unable to breathe through their mouth, because the trachea is not connected to the whales throat.
This separation is important for a number of reasons.
First having a separate hole for breathing and eating allows whales to minimize the likelihood of blocking their air passage due to food trapped in their throat. Meaning it’s very hard for them to choke on food, the way we humans would.
More importantly, having a separate air passage and food passage means that whales are able to swallow their food underwater without worrying about taking water into their lungs, meaning that they are less likely to drown as they eat, unlike other land animals, who don’t have this separation between air passage and digestive tract.
If a human were to try and consume food underwater there is a chance that water would infiltrate the air passage and end up in the lungs.
Secondly, by having the blowhole situated on the top of the whales’ head they can take in oxygen without having to lift their head above the water or exert additional energy.
To assist with long dives whales have developed special lungs that help them inhale additional oxygen and transfer it to enlarged blood vessels, where it can be used by the body slowly over time.
According to some researchers whales are also able to use up to 90 percent of the oxygen they inhale, as compared to humans that are only able to use around 15 percent of the oxygen they inhale.
Whales are also extremely efficient swimmers and use minimum effort to travel and hunt for food, in order to conserve precious oxygen.
In terms of how long a whale can hold its breath varies depending on the species of whale.
Some species can only hold their breath for only a few minutes before resurfacing for air, while other whales can hold their breath for up to 90 minutes or more.
Due to the fact that whales live in the ocean, they’ve developed a way to maintain their awareness of their surroundings and maintain control of their breathing, even when at rest.
In fact whales are considered conscious breathers because they never fall completely asleep and they must frequently come up for air otherwise they could drown and die.
During periods of rest, half of the whales brain will shut down while the other half of their brain remains alert in order to react quickly to life-threatening situations, such as resurfacing for oxygen or running from predators.
When a whale surfaces from a long dive it is common to see water spouting from the whales blowhole which is a sign that the whale is exhaling.
In the past people thought that the water coming from the blowhole was water that the whale swallowed or inhaled, however this is not the case because if a whale inhaled the water it would likely enter their lungs and the whale would drown, and since the throat is not connected to the blowhole it is virtually impossible for a whale to spurt out water that it swallowed through its mouth.
The water that spouts from the blowhole is simply water that has collected around the outside of the blowhole, and it thrown into the air with the vigorous exhalation.
The whales blowhole is surrounded by muscles to allow the whale to dive without fear of inadvertently breathing underwater.