Mermaids are mythical creatures that have the upper half of a human female and the bottom half of a fish. With the ability to breathe above and underwater, where mermaid sleep can be a confusing question.

Though the exact answer will depend on the heritage and tradition you look at, all mermaids sleep underwater.

Let’s take a closer look at mermaids, where they sleep, and how they sleep.  

Mermaids have been a part of international folklore for centuries. Most stories are slightly different from one another, but one similarity remains.

No matter what tradition you look at, mermaids always sleep under the water. This includes mermen too. Sleeping underwater ensures that mermaids do not get dehydrated and remain safe from enemies like humans.

Where Can Mermaids Sleep?

As we have already mentioned, there are different ways that a mermaid can sleep underwater, depending on the tradition. In most stories, mermaids sleep on seaweed beds underwater. This allows the mermaid to be similar to humans while still retaining a few of their fishy elements.

Similar to a seaweed bed, some stories say that mermaids sleep on a giant stone. These stones can either have or lack seaweed. In either case, the stones look like a bed, but they can be used for other purposes too, such as perching when the mermaid is awake.

A few mermaid stories also describe them as sleeping in underwater or island caves, though there are way fewer stories that depict this sleeping location than the previously mentioned two.

How Do Mermaids Sleep?

How exactly mermaids can sleep underwater depends on the folklore source you look at. There are typically two different depictions of mermaids. One implies that they are water mammals, while another implies that they have gills like fish.

Some depictions of mermaids make them appear endothermic. In simpler terms, they are underwater mammals, more like a dolphin than a fish. Like a dolphin, mermaids can hold their breath for a long time to remain underwater.

Within these stories, mermaids can sleep underwater by holding their breath. With this logic, they must be able to hold their breath for a long time, and they likely don't sleep for long periods at once.

Other depictions of mermaids portray them as actually breathing underwater, not just holding their breath. In some folklore, mermaids have gills like fish. This allows them to breathe underwater, while their mouth, nose, and lungs let them breathe above water as well.

Most often, folklore involving sleeping mermaids takes this approach to their anatomy. They simply sleep underwater just as we sleep above water. They continue naturally breathing, thanks to their fish-like gills.

Origins and History

The word mermaid translates literally to ‘sea woman,' and their depiction remains somewhat conflicting; some of the time, they were depicted as delightful, alluring ladies who were significantly desired by forlorn sailors, while likewise being given a role as monsters that hauled men into the dark, inky depths of the ocean.

Mermaids, conventionally, have the head and upper body of a female human and a tail of fish. Their mentions can be found throughout history ranging from the Greek gods to the extensive world of Hinduism.

You may ask how mermaids came to be, and for what reason did such countless individuals around the planet envision them forever? It's a fascinating question that most likely has more than one answer.

The mythical creatures' origin is not absolute; as mentioned earlier, while mythological origins abound, a common modern-day consensus is that their existence originates from when the oceans were unexplorable stretches that hide mysteries beneath their surfaces.

Mermaids are thought to be half-mammalian and half-aquatic mythical creatures. It isn't easy to establish which half would dominate. On the one hand, they speak, look, and react as humans would. Then on the other, they live and breathe under the sea. 

One thing's for sure - whether they're more human than fish or vice versa, mermaids would ultimately have to call it a day and retreat to sleep. Why? Because both humans and underwater dwellers need their sleep. However, their mode of sleeping is different.

Humans go on 'autopilot' mode when they sleep. They aren't necessarily non-functioning but would require a longer reaction time. In effect, humans 'switch-off' the active part of their minds. There are two types of sleep for humans; Random Eye Movement (REM) sleep or Deep Sleep.

On the other hand, fishes sleep with one half of their brain turned off at a time. For this text, we're referring to the aquatic half of mermaids as closely resembling mammalian life forms such as dolphins, seals, and whales.

Sleeping With One Half of Your Brain

It was generally believed that deep sleep was a characteristic of humans. The mode of sleep that can be well described as perhaps the best type is what all mammals enjoy - albeit with some differences. Deep-sea animals such as dolphins, whales, and seals sleep with one half of their brain at a time. 

It sounds counter-intuitive to the whole idea of sleep. One portion of their cerebrum is conscious, including an open eye, and the other half is at rest. In all likelihood, this is a defensive system, empowering the creature to fly or swim and screen its current circumstance for dangers with one side of the equator while different gets some rest.

Based on their habitats and instinctive animal qualities, it is, therefore, safe to assume that mermaids too sleep with one half of their brain at a time.

Mermaids or merfolk are once called because not everyone is female, has a long history, and is known everywhere globally – similar way winged serpents, fairies, and unicorns are.

Just how old is the idea of mermaids is unknown, and it might have originated with the earliest interactions between humankind and marine life. Archeologists have discovered records in Mesopotamian folklore of a male fish god from more than 5,000 years ago.

Some of the first known mermaid legends showed up in Syria at around 1000 BC. The goddess Atargatis jumped into a lake to appear as a fish. As the divine beings that would not permit her to surrender her extraordinary magnificence, just her base half turned into half-aquatic. She kept her other half in human structure. This is supported by the discovery of Atargatis' figure on antiquated sanctuaries, sculptures, and coins.

Some people have argued that the merpeople represent a more primitive form of humans. However, merpeople are their line and breed of humanoids. How long do mermaids live?

Regarding how they sleep, one might argue that they morph back into their full human forms and sleep on land. The hassle, however, wouldn't be one a mermaid would want to go through daily.

For this reason, it's more probable for them to sleep similar to their underwater mammalian counterparts - with one-half of their brain at a time. 

Final Thoughts

Most folklore depicts mermaids as sleeping underwater in beds made of seaweed or rock.

Although there is the occasional story of mermaids sleeping elsewhere, such as in an underwater cave, all mermaids typically sleep underwater.

This underwater sleeping location allows them to remain safe and utilize their fish half.

Could there be a logical reason behind this lore? Few scientists argue that sightings of creatures, such as manatees, might have led to the creation of these myths owing to their human-size anatomy with a fish-like tail and two flippers that can be misconstrued as arms.

While they don't resemble the beauties described in texts up close, they are quite the contrary, and it should be noted that most of the sightings back in the day were from a severe distance away, with the view partially obscured by the waves and the mist.

Throw in the dim illumination provided by the stars and the moon at night, emphatically distinguishing even a realized animal can be troublesome. A brief look at a head, arm, or tail not long before it plunges under the waves may have generated some mermaid reports.

Also Read: What Mermaids Eat