How Do Sea Snakes Breathe?

While most snakes live on land and occasionally swim in the water, sea snakes spend their entire lives in the water. 

Why are they so different from your average snake?

How do sea snakes breathe? 

Sea snakes, like other snakes, require air to breathe despite living in the water. They must occasionally resurface to fill their lung with air. However, they also have specific adaptations which allow them to remain underwater longer than the average snake.

If you’re interested in learning more about sea snakes and their unique characteristics, continue reading through this article. 

Sea snakes are amazing creatures and have fascinated scientists for decades.

banded sea snake underwater in the ocean

What Are Sea Snakes?

Sea snakes are a venomous breed of elapid snakes which mainly thrive in marine environments for their entire lives. 

They evolved from land snakes and still possess some of the qualities of their land-bound relatives. 

Sea snakes live in warm coastal waters, and certain species are known to possess some of the most potent venoms. 

Most sea snakes cannot move on land and will be entirely stranded if they ever wash up on shore. 

This is because their bellies do not have “scutes,” which are a special version of scales responsible for a snake’s ability to grip the ground and slither. 

Instead, they have a tail described as “paddle-like” which allows them to glide through the water, making them appear more like an eel than a snake.

How Do Sea Snakes Breathe?

Sea snakes have developed precise mechanisms of breathing which differentiate them from other species of snakes. 

Although they live in water, sea snakes require air to breathe. 

Their nostrils breathe in the air when they resurface, and then close back up once they dive underwater, similar to the blowhole in whales; this unique variety of nostrils is called “valved” nostrils. 

These are located on the top portion of the snake, so it’s able to remain almost entirely underwater when it comes to the surface. 

To preserve the air they breathe, sea snakes have developed one extremely long lung—also known as a saccular lung— which pretty much takes up their entire bodies. 

In addition to helping with air storage, this lung also assists with a snake’s buoyancy in the water.

Do Sea Snakes Have Gills?

Not exactly. 

Gills are respiratory organs specific to aquatic organisms used to extract oxygen from the surrounding water and release carbon dioxide. 

In fish, these are the parallel slits you see next to their mouths and eyes. 

Sea snakes do not have gills like aquatic animals, but they have a gill-like blood vessels network. 

A recent study in Australia used technical imaging to understand the bodies of sea snakes better and discovered a network of blood vessels just underneath the skin of the forehead and snout. 

The theory developed by scientists states the blood in these vessels can absorb water through the skin and utilize its oxygen. 

This blood travels directly to the sea snake’s brain. 

This is probably why sea snakes can survive underwater for a substantially longer period than most air-breathing animals. 

It’s pretty much able to “breathe” underwater, although to a more limited capacity than other aquatic animals. 

Unlike animals with gills, though, sea snakes must resurface to breathe regular air and cannot permanently live underwater without some breaks. 

Further research is required to elucidate better how sea snakes can breathe for so long underwater.

How Long Can Sea Snakes Stay Underwater?

Sea snakes can generally stay underwater for anywhere between one to three hours and dive to depths over 200′ feet (61 m) deep. 

When they do have to resurface, they only need to be up there for about 45 seconds to collect air before diving right back into the water. 

This is an excellent adaptation to help them spend more time hunting for food, of which they prefer eels.

Do Any Sea Snakes Come Onto Land?

As mentioned before, most sea snakes lack the necessary belly scales to facilitate slithering on dry land, making them utterly incapable of surviving on land. 

Only one genus of sea snake has retained these scales: the Laticauda, of which sea kraits are the most popularly known type. 

This species still comes to land to lay its eggs, whereas other species of sea snakes are ovoviviparous, meaning they incubate eggs inside of themselves and give birth to live snakes. 

This is an essential adaptation for sea snakes, as the thin shells of eggs make them permeable to water. 

If they are laid underwater, the baby snakes inside will drown.

Can I Get A Sea Snake As A Pet?

No, sea snakes would not make for good pets. 

Most species are venomous, making them dangerous to humans. 

Although most sea snakes only bite if they are provoked, it is still not recommended to care for one in your home. 

Check out our other blogs on the best snakes for handling if you’re interested in buying yourself a snake as a pet.

Conclusion

Sea snakes are an exceedingly cool and unique species of snake, and now you know how sea snakes breathe. 

Like all snakes, they require air to breathe and survive. 

However, unlike other snakes, they can stay underwater for hours at a time, likely due to the network of blood vessels underneath their skin, which allows for direct oxygen transfer through the skin.