Whales along with other species ,are known for being mammals that live in the sea. To understand how they breathe we should know first, that their anatomy has features ;which allow them to breathe air from the surface while they are swimming. This sort of animals are known as cetaceans, which include eighty species; divided mainly between the families of cetaceans with teeth and cetaceans with baleen. Dolphins are a good example of the first group and whales belong to the second one, as the minke whales for example .All these animals have the peculiar property of breathing air through their nostrils.
Whales´ Breathing Process
First, the whales caught air direct from the surface, through the holes at the top of their head. This hole is called spiracle, and it´s part of the respiratory system of these species. This is the reason why whales, in spite of being adapted to the water; need to emerge to be able to breathe regularly.
Some of them have only one, as the case of toothed whales. In the case of the baleen whales they have two spiracles, located on their head. Blue whales are a good example of whales with two spiracles., Now, once the whales have caught air from the surface , they can continue swimming and dive. Depending on the species, they can maintain the air from 20 minutes to two hours; since they use 90% of the oxygen that has entered their lungs, which is a big advantage.
Then whales return to the surface, to expel from their body; the water vapor along with mucus that has formed in their lungs. This vapor usually gets compacted resulting in a spout that can be easily observed in this process. This is because it’s very hot, and the tropical temperature where whales commonly live, make it condense . So, it looks like a huge water jet
Thus, according to the entire process previously mentioned, we can say that it is lung breathing. It should be noted that although this process resembles that of humans, the difference is that for whales it is impossible to breathe through their mouth. But undoubtedly, the breathing process of whales, can be described as the most efficient compared to other mammals.
Spiracle: Main Characteristics
These holes are surrounded by a ridge that is usually thick, preventing this way the presence of water while the animal breathes on the surface.
The nasal septum that divides the two spiracles, ( depending on the species) ; has two valves attached, which can open and close to prevent water from entering through the nostrils, when the whale is submerged in the sea. Many studies have led to the conclusion that, it is a voluntary act of the whales, since they are the ones who decide when to generate the action of opening and closing according to their breathing. This means that the breathing process of whales is carried out consciously, and in the same way as the dolphins, these animals do not sleep completely.
Another important feature of the spiracle , is that it allows the whale to breathe a large amount of air; that in proportion means 85% of its lung capacity. This is another important aspect, since after the whale is submerged again in the water, this animal usually reduces its heart rate in order to take full advantage of the oxygen that it has breathed on the surface during its swim
Finally, we invite you to watch this illustrative of How do Whales Breathe