Whales are one of the most fascinating animals that we can find in seas and oceans around the world. This family of aquatic mammals belonging to the order of Cetaceans includes some 86 species, among which we can find the impressive blue whale, the largest animal of all those that have ever inhabited our planet; as well as the humpback whale and the southern right whale, both surprising for their amazing jumps on the surface of the sea.
Where do whales breathe?
All whales breathe through their nostrils , which are called blowholes . These holes have nerve endings that allow the animal to recognize if it is out of the water and are located on the top of the head . This location of the spiracles allows the whales to breathe with practically no effort, being able to remain resting on the surface of the ocean and capturing the oxygen they need to live.
The spiracles appear covered by a membrane that acts as a valve, which in a relaxed position of the muscle keeps the orifice sealed, preventing the entry of water into it.
On the other hand, it should be noted that the nostrils are not connected to the animal’s mouth, and therefore they are not able to breathe through the mouth . In this way, the whales are assured of a feeding process independent of respiration, so that no water reaches their lungs while they are eating.
The breathing process of whales is as follows:
- Despite living in aquatic environments, whales need oxygen from the air present in the atmosphere to breathe, as do all land animals. With each new intake of air, the whales are capable of acquiring up to 85% of their total lung capacity.
- Once the air has entered your nostrils through the blowhole located in your head , it is conducted up to the windpipe.
- From the trachea the air passes to the lungs , where the oxygen they have taken from the atmosphere will start their breathing circuit.
- Oxygen is carried from the lungs by the blood and eventually converted to carbon dioxide.
- Carbon dioxide is expelled along with nitrogen through the same blowhole, thus closing the circuit of respiration.
This last step of the respiratory process, the exhalation, is the moment in which the whales expel carbon dioxide and we can see on the surface torrents of water that emerge from the blowholes of the whales in the form of columns of water and air.
Within the breathing process, whales acquire various strategies to facilitate it and to save oxygen and be able to last longer underwater .
Bradycardia in whales
Bradycardia stands out, for example, a process by which whales decrease their heart rate , which is directly related to a lower oxygen demand, thus being able to remain submerged in the water for a longer time before carrying out the next inhalation. In addition, whales have a high tolerance to carbon dioxide, so they can keep it in their body for longer periods of time than in the case of humans, before each exhalation.
More oxygen for vital organs
Another strategy that whales use to optimize respiration is by sending oxygen through the blood only to the vital organs that need it, such as the brain, heart and muscles used to swim; thus conserving oxygen in your body for a longer time.
Whales are not able to sleep soundly , since in that case they would stop breathing. We can say then that your breathing is always conscious .
The muscles of the lungs and other organs involved in the breathing process perform their functions in a controlled way by the nervous system, which is always alert to be able to distinguish any dangerous situation, both due to the presence of predators and the the need to resurface to breathe , due to the need to inhale oxygen or exhale carbon dioxide.