Something tells me the question, “How do whales sleep underwater?” doesn’t invade your mind too much. But once you think about it, you really want to know! After all, as marine mammals, whales still need to surface for air, which seems difficult during a long nap!
Let’s take a deep dive into how whales sleep!
How do whales sleep?
Among cetaceans (the group of animals that includes dolphins and porpoises), whales are behemoths. They are also mammals, and their lungs need oxygen, so whales need to come out of the water to breathe.
Blue whales are the largest animals in the world, weighing up to 440,000 pounds. So how can something this big, needing air in its lungs, sleep without drowning?
Here are two ways whales sleep underwater:
- Stay still on, near or further away from the surface.
- Swim slowly next to another animal.
It’s important to watch out for whales sleeping different More than most mammals on land. While many land mammals have developed adaptations that allow them to sleep standing up, whales have an adaptation that allows them to rest while breathing — every 3 to 15 minutes, depending on the species of whale.
How do whales’ brains and bodies work while they sleep?
It’s easy to think there’s only one way to sleep — the human way, but that’s not the case for all creatures.
As mentioned earlier, One of the ways whales sleep is on or near the surface of the water. This is an act called “recording” because they stand still and can be mistaken for recording.
Another recorded form of sleeping is hanging upside down, not moving and not breathing. Human breathing is unconscious. Whales are not. Cetaceans need to consciously know when to breathe because they need oxygen and water.
They also only use half of their brains to sleep and half to stay awake. Talk about dividing. Whales usually only close one eye. The reason may be because they need to be vigilant against predators, but also because they can’t lose much body heat which sleep noticeably affects.
The amount of time they sleep varies from species to species. Scientists have found that some people take naps in 10-15 minute increments. (Cat napping?) But humpback whales have been spotted sleeping on the surface for up to ½ hour.
While more research is needed on the sleeping habits of whales, it is believed that different species have different sleep needs. For example, sperm whales are thought to sleep less than two hours per day, while some dolphin species have been observed to sleep for a similar amount of time to humans, namely eight hours per day.
How do whales sleep
Did you know that calves (baby whales) would actually sink if it wasn’t for one thing: their mother! Mother whales don’t stop swimming during the weeks of their calf’s life. If she did, her babies would probably sink because they don’t have the fat/fat they need to float.
While the mother swims, her calves rest, eat and sleep in her air currents. This is called echelon swimming. It’s a bit like driving a semi on the interstate. The aerodynamics are such that it creates a suction that draws you in.
The little ones can’t swim great distances yet, so their mum works with them to teach them and help them build their strength and fat reserves. Keep in mind that if the calves are weakened from swimming too much, they may endanger themselves and the pods as they may attract the attention of predators.
Sleeping Habits of Sperm Whales
There are amazing pictures of sleeping whales. In 2017, photographer Franco Banfi captured a pod of sleeping sperm whales while freediving (without rebreathers). They were motionless, lying vertically on the water. Hard to believe without photo proof.
While diving off the coast of the Dominican Republic, Banfi suddenly finds himself among sleeping giants. They drift about 65 feet below the surface.
“Other whales joined the group from below us and we found ourselves among them. The calves were protecting in the middle of the group and suddenly they all stopped swimming and started sleeping vertically in the water.”
Award-winning photographer Franco Banfi from Amateur Photographers
However, this isn’t the first time this behavior has been seen. In 2008, researchers published a study describing this strange sleeping habit found in the wild. They also reported that the whales were not breathing or moving while they were sleeping.
at last……
How whales sleep underwater still requires more research and is far from exhaustive. In the course of my research, phrases like “a general hypothesis…” and “it’s not clear whether…” and “…is still a matter of discussion” kept popping up.
Not much information available on this topic!
We may never know every single whale’s sleeping behavior, but maybe it’s not so earth-shattering that we don’t understand what’s going on in the vast ocean world. I think the whales have everything under control.
I am broadly interested in how human activities influence the ability of wildlife to persist in the modified environments that we create.
Specifically, my research investigates how the configuration and composition of landscapes influence the movement and population dynamics of forest birds. Both natural and human-derived fragmenting of habitat can influence where birds settle, how they access the resources they need to survive and reproduce, and these factors in turn affect population demographics. Most recently, I have been studying the ability of individuals to move through and utilize forested areas which have been modified through timber harvest as they seek out resources for the breeding and postfledging phases. As well I am working in collaboration with Parks Canada scientists to examine in the influence of high density moose populations on forest bird communities in Gros Morne National Park. Many of my projects are conducted in collaboration or consultation with representatives of industry and government agencies, seeking to improve the management and sustainability of natural resource extraction.
