While snakes are associated with various biomes, from deserts to forests to swamps, most people don’t consider snakes aquatic creatures. Almost all snakes are capable swimmers, but do they face the same risk of drowning as other land animals?

Snakes can drown if they get stuck underwater and can’t reach air. Like all land-based animals, snakes need air to breathe. Even aquatic snakes that live in or near water need air to breathe and are thus susceptible to drowning.

In this article, I’ll explain how snakes breathe and survive underwater, even without gills. I’ll also cover aquatic snakes that spend most of their lives in or near water.

Can Snakes Breathe Underwater? 

Water-based animals use gills to absorb oxygen from water. However, snakes rely on their lungs for oxygen, which they get from the air. Thus, they have to hold their breath and come up for air when swimming, like whales.

A snake gets air into its lung in two ways.

• They breathe through the nostrils on the snout.
• They use a structure found behind the tongue known as the glottis.

The glottis is a small opening in the mouth that opens when they inhale. It connects directly to the windpipe.

When they feed or constrict prey, snakes can use different ribs to keep their lungs pumping. This ability allows them to keep breathing even when their ribcage expands to capacity.

Snake Lungs

Most snakes only have a single, functional lung that extends through most of their torso. Aquatic snakes have longer lungs that allow them to hold more air, while land-based snakes have slightly smaller lungs.

Can Sea Snakes Breathe Underwater? 

If snakes have lungs and can drown, how do sea snakes live the vast majority of their lives underwater? The answer relies on two parts – not only do these species have a longer lung than terrestrial snakes, but they can also absorb oxygen through their skin. 

A study from 2019 found that Blue-Banded Sea Snakes have a very odd blood-vessel network on the top of their heads. The blood in these vessels is low in oxygen compared to the surrounding water, so the oxygen diffuses from the water into the blood and then moves to the brain.

These snakes still hold their breath and need to come up for air, but much less frequently than others. While most sea snakes don’t have the ability to absorb oxygen through their skin, they still have longer lungs that let them hold more air.

When Will a Snake Drown?

Even the best swimmers can drown, and snakes are no exception. They can die if they get stuck with their head underwater. Sea snakes will also drown if they can’t reach the surface in time to breathe, which could happen if they become too tired to swim.

If you have a pet snake, make sure there is no way they can get stuck in their water dish. If you have a pond or pool that your snake likes to soak in, keep an eye out to ensure it doesn’t get stuck underwater.

Conclusion

Snakes need air to breathe and can drown if left underwater for too long. Even true sea snakes, which hunt and give birth underwater, hold their breath when swimming.

While some sea snakes, like the Blue-Banded, have a network of blood vessels that act like gills and can stay underwater for hours, they will still need to come up for air. In that way, snakes manage a lot like whales.

While snakes are as vulnerable to drowning as other gill-less animals, this is another example of how adaptable and versatile they can be.