Do Sharks Sleep?

Sharks are some of the most interesting creatures on the planet. Some are among the largest predators in the ocean. They are also vital to the ecosystems and food chains of the sea. Many of them are also among the animal species in danger of going extinct.

As much as we are fascinated by sharks, there is a lot we do not know about them. People devote their lives to studying different types of sharks, and discoveries occur all the time.

The knowledge about sharks sleeping is one place where there is still a lot to learn. Researchers are still working on learning more about sharks and their rest habits. Much of this is due to the fact that it can be difficult to study sharks in the deep seas. Technology is now making this type of research more accessible.

With this post, we will look at some of the facts known about how sharks sleep and rest.

Can sharks stop swimming?

Do sharks sleep? Before we answer that question, we need to consider some facts about sharks and their biology. For a long time, it was believed they could not sleep because they need to keep water moving over their gills for respiration.

While some sharks rely on ram ventilation to breathe, there are adaptations that allow some to stop swimming. Even the ones that rely on ram ventilation may have strategies that allow them to rest still for a time.

Shark Adaptations

How do sharks sleep if they need to keep moving for respiration? Some species of sharks have various adaptations that allow them to breathe even when they are resting still. Many sharks can use a method of respiration known as buccal pumping. Instead of having to swim to keep water moving over their gills, these sharks pump water through their mouths, allowing sleeping sharks to get the oxygen they need.

Some sharks like great whites or makos lack the muscles for buccal pumping. They rely entirely on ram ventilation. However, researchers recently observed a great white shark in what appeared to be a state of sleep or rest. The shark was floating with its mouth open facing the current. This could be a way for ram ventilators to breathe while resting.

Do sharks sleep?

The answer is that sharks do sleep, but their sleep is different from what we would consider sleep in other animals. We now see that most sharks can stop swimming for a time and rest. Depending on the species, they have different adaptations and strategies that allow them to maintain respiration when still.

Earlier this year, researchers published findings about sharks they observed in a sleep-like state. During the research, they observed various characteristics that indicate shark sleep. Most notable were the change in posture and a lower metabolic rate. Based on these findings, it appears that sharks do sleep.

Do sharks sleep with their eyes open?

There are animals that sleep with their eyes open. The researchers that observed sharks in a sleep state noted that shark eyes are not a good indicator of sleep. The eyes may open or close at different points when a shark is sleeping. The reason sharks do not close their eyes during sleep is that their eyelids do not cover the entire eye like ours. Furthermore, their eyelids serve more of a protective function.

Where do sharks sleep?

The answer to that question depends on the type of shark. Some sharks have been observed resting on the ocean floor. Some might find caves or other secluded places to rest. Some sharks might just float as they sleep. It is also believed that some shark species engage in a form of sleep swimming. There is still a lot more for scientists to discover about the shark sleeping habits.

Shark Conservation

Shark conservation is an important issue for the team at Fahlo. That is why we donate a portion from every sale of our Voyage Shark Tracking Bracelet to Saving the Blue. Along with the bracelet and donation, each sale comes with information about a shark you can track. Learn the shark’s name, see their picture and track their location.