Instead, they have a fascinating adaptation known as 'unihemispheric sleep'. To be able to sleep, whales shut down half of their brain at a time. Being partially awake allows them to continue breathing and be aware of their surroundings. Whales will usually stay in place as they sleep near the surface.
The cetacean also maintains control of its blowhole, the orifice on the top of its head that is the equivalent of our nostrils. This fold of skin is voluntarily opened by the animal, which contracts the muscles around its blowhole whenever it takes a breath. The two hemispheres of the brain alternate periods of rest.
Humpback whales are often found resting motionless on the surface of the ocean while sleeping. They cannot sleep for much longer than 30 minutes without risking lowering their body temperature due to inactivity. A very common assumption is that whales sleep with half of their brain 'shut off' and one eye closed.
Observations of bottlenose dolphins in aquariums and zoos, and of whales and dolphins in the wild, show two basic methods of sleeping: they either rest quietly in the water, vertically or horizontally, or sleep while swimming slowly next to another animal.
The whales were found to spend seven percent of their day in these vertical sleeping positions near the surface of the water, where they napped from 10 to 15 minutes. Researchers suggested at the time that they might be one of the world's least sleep-dependent animals.
The mammal that sleeps the least is the African bush (savannah) elephant Loxodonta africana, which has been found to sleep only two hours per day on average – less than any other mammal species so investigated.
How Do Whales Close Their Eyes? Another very interesting fact about whales is how and when they close their eyes. Because it is so laborious to do so, the eye typically only closes when the whale is sleeping.
Instead, they have a fascinating adaptation known as 'unihemispheric sleep'. To be able to sleep, whales shut down half of their brain at a time. Being partially awake allows them to continue breathing and be aware of their surroundings. Whales will usually stay in place as they sleep near the surface.
The koala holds the accolade for 'the animal that sleeps the most'. This Australian icon sleeps for 20-22 hours each day (sounds good to us), making it the sleepiest creature in the animal kingdom.
The longest ever recorded dive by a whale was made by a Cuvier's beaked whale. It lasted 222 minutes and broke the record for diving mammals. Other whales can also hold their breath for a very long time. A sperm whale can spend around 90 minutes hunting underwater before it has to come back to the surface to breathe.
Whale wizz
When it comes to pee production, whales are world champs. A single fin whale is thought to produce around 1,000 liters (260 gallons) of urine each day — enough to fill a 10-by-6-foot kiddie pool. Whales combine their champion urination with deep dives and long migrations.
Most species of whale are known to spend their time doing a variety of activities including foraging, migrating, mating, socializing, sleeping and exploring.
On average, larger whales will surface for air about every 10-15 minutes. Smaller whales usually won't stay underwater for more than 5-minutes.
Whales possess a varying number of teeth, depending on the individual species. Some kinds of whales only have one or two teeth, while others might have 240 teeth or even more. Dental patterns can vary. Some toothed whales have teeth in both their upper and lower jaws.
Because whales are mammals, their calves grow inside their mothers and are born through live births. During the whale birth process, calves will emerge fins first. The size of a whale calf will depend on the size of the mother, but generally speaking you can expect it to be about ¼ the length of the mother.
Whales have an incredibly thick layer of insulating blubber. Without the water to keep them cool, they overheat and lose too much water via evaporation from their lungs.
Snails need moisture to survive; so if the weather is not cooperating, they can actually sleep up to three years. It has been reported that depending on geography, snails can shift into hibernation (which occurs in the winter), or estivation (also known as 'summer sleep'), helping to escape warm climates.
Koalas. Hats off to the (somewhat disputed) king of sleep: the Koala bear. They've been reported to sleep up to 22 hours a day in captivity, over 90% of their lives.
Gray whales are known to be very curious and inquisitive, giving them reputation of being the “friendly” whale. They often swim right up to boats and poke their heads vertically out of the water to get a better view of their surroundings in a behavior called spyhopping.
As a child, you may remember squealing and screaming when you were excited about something. It turns out that humans aren't the only species that gets noisy when they're happy: New research shows that whales and dolphins “squeal with delight” to express glee, too.
Whales are colour blind
They can distinguish light from dark, but, like humans who are colour blind, they cannot tell the difference between red and green on a traffic light. Indeed, the eyes of cetaceans are monochromatic.
The answer is: they do not drink water like land animals do, as they don't risk dehydration from the sun. This goes for all the marine mammals like whales, dolphins, seals etc. The way they get water is through their food.
In general, whales stay at the surface or close to the surface of the water while they're sleeping. This allows them to easily come up for air when needed. Whales are also very buoyant because of the amount of blubber in their bodies. This helps them continue to float while sleeping without worrying about sinking.