Whales are the giants of this planet that we don’t get to see very often – some people never lay eyes on these creatures in their entire lives.
As such, not much is widely known about whales and how they live or even how they sleep. Humans, cats, dogs, and most other animals sleep in similar ways.
Normally, we will lie down, close our eyes, and eventually fall asleep. However, for the animals of the ocean, things happen differently. It’s not like they can just lie down and expect the currents not to sweep them away.
Fortunately, those curious about just how whales rest can now get a glimpse thanks to the work of a talented photographer.
The footage captured on film is quite a sight to see.
Not The First Photos
Although not many of us have seen whales sleeping, there has been visual evidence captured in the past.
While freediving in the Caribbean Sea, photographer Franco Banfi was able to take a photo of a group of six sperm whales taking a nap.
The whales were close together, suspended in the ocean water. They had their tails down and were completely quiet.
They were at a depth of about 20 meters, or 65 feet.
Almost two weeks later, Stephane Granzotto, a French photographer and filmmaker, caught whales doing the same thing.
Stephane was diving in the Mediterranean Sea.
It was back in 2008 that scientists first began to document this strange way of resting. The Current Biology journal published a study that measured the underwater activity of 59 whales worldwide.
Data-logging tags that were suction-cupped to the animals were used for more than 569 hours of data recording.
According to the information gathered, whales spend roughly seven percent of their day sleeping. However, they do not rest all at once.
Instead, they sleep in increments of ten to 15 minutes at a time. As such, whales are the least dependent on sleep animals in the world.
Additionally, the study found that the vertical position for sleep is done by all whales.
Previously, scientists studied the sleeping patterns of whales that were in captivity. They monitored brain activity through an electroencephalogram as well as observed the animals’ eye movements.
Of course, this cannot be done with wild whales.
How Do Whales Sleep, Exactly?
Humans can sleep for long periods thanks to the fact that we are passive breathers – we don’t have to think about breathing. Our lungs are told by our brain what to do, and we breathe automatically.
There is no risk of not breathing when we sleep. For whales, this is not the case.
Whales need to think about every single breath that is taken actively. Because of this, they fall into unihemispheric slow-wave sleep.
That means whales sleep only with half of their brain. While one half of their brain is resting, the other half keeps the animal aware of its surroundings. This way, they can avoid predators and maintain contact with each other.
Whales cannot breathe underwater, which is why they can only sleep for such short amounts of time.
Scientists have not yet learned all they can about whales in the wild. As a result, it is not easy to say whether or not whales in the wild behave the same as those in captivity.
They also do not sleep in the same ways. One example of this is when a group of whales were sleeping off the coast of Chile.
A boat approached them, but none of the resting animals woke up or moved out of the way. Only when the vessel inadvertently bumped into them did they wake up and scatter.
This may mean that wild whales may be able to enter full sleep, unlike what has been observed in captive whales.
Sperm whales have a unique way of sleeping that was noticed by observers. They will dive head-down to a depth in the ocean that is deeper than the length of their bodies.
Then, the animals passively turn their heads upward and drift towards the surface. This gives them a chance to rest.
It is interesting to note the various ways that animals in the ocean get their beauty sleep, but further study is required.
To get a better idea of the true sleeping patterns of whales, more research needs to be done.