Can Sharks Live in Freshwater? The Myth Busted

  • By: Alex
  • Date: July 29, 2022
  • Time to read: 7 min.

Sure, sharks can technically live in freshwater environments. But it’s not exactly ideal for them. For one thing, most shark species are marine animals, meaning they’re used to saltier water. It’s thought that only certain types of sharks (like bull sharks) can tolerate living in freshwater for an extended time.

Sure, sharks can technically live in freshwater environments. But it’s not exactly ideal for them. For one thing, most shark species are marine animals, meaning they’re used to saltier water. It’s thought that only certain types of sharks (like bull sharks) can tolerate living in freshwater for an extended time.

Even then, they don’t do well in freshwater for long because their bodies aren’t built for it. Freshwater is less dense than seawater, so a shark swimming in freshwater would actually use up more energy than it would in saltwater.

This can eventually lead to exhaustion and death. So while sharks can technically survive in freshwater, it’s not a good idea for them to do so for very long.

Why can some Sharks live in Freshwaters?

Why can some Sharks live in Freshwaters?

There are various reasons why some sharks can live in freshwater while others cannot. One reason has to do with the origins of sharks.

  1. The earliest ancestors of sharks lived in freshwater environments, so they have adapted over time to be able to live in both salt and freshwater.
  2. Some shark species are born in freshwater rivers and then migrate to saltier waters as they mature. This flexibility gives them a more extraordinary ability to survive in different environments.
  3. Some sharks have specially adapted kidneys that allow them to filter out salt from their bodies and remain healthy in freshwater. This adaptation is seen in the bull shark, one of the few species that can live comfortably in salt and freshwater.

For these reasons, sharks can thrive in many environments, including freshwater rivers and lakes.

Why can’t saltwater sharks live in freshwater?

How many sharks can live in freshwater?

Have you ever wondered why you never see saltwater sharks swimming in freshwater lakes or rivers? The answer has to do with the way these sharks regulate their internal salt levels.

Unlike other fish, sharks must retain salt inside their bodies to survive. This is because their cells are held together by a thin layer of water; if they lose too much salt, the cells will begin to swell and rupture.

As a result, most sharks cannot enter freshwater environments without suffering from bloating and death.

How many sharks can live in freshwater?

While most sharks prefer salt water, a few species can adapt to life in rivers and lakes.

The Bull Shark

Bull Shark

The Bull Shark is one of the most well-known freshwater sharks. This species is found in many major rivers, including the Amazon, the Ganges, and the Mississippi. The Bull Shark can tolerate a wide range of salinity levels, and it often enters brackish waters where salt and fresh water mix.

This adaptability has helped the Bull Shark to become one of the most widespread sharks in the world. In addition to its global distribution, the Bull Shark is also notorious for being one of the most aggressive shark species.

Attacks on humans are relatively rare, but they tend to be fatal when they do occur. For this reason, the Bull Shark is considered one of the world’s most dangerous sharks.

Ganges sharks

The Ganges Shark is a river shark that is found in the Ganges river in India. These sharks are large and can grow up to 18 feet in length. They are brown or grey in color and have small eyes. The meals of these sharks include fish, crustaceans, and mollusks.

These sharks are dangerous to humans as they have been known to attack people swimming in the river. However, they are not considered aggressive and usually only attack if they feel threatened.

Northern river sharks

The northern river shark is a requiem shark found in Australia, New Guinea, and Indonesia. Despite its name, this shark is more likely to be found in saltwater than in freshwater bodies of water.

Adults reside primarily in coastal seas, while juveniles frequent rivers. This is because juvenile sharks need to avoid predators, and the shallow waters of rivers provide them with ample places to hide.

As they grow older and become large enough to defend themselves, they move out into the open ocean, where they can find more significant numbers of prey.

Although they are not typically considered dangerous to humans, northern river sharks occasionally attack swimmers and boaters.

Speartooth sharks

Speartooth sharks are one of the few species of shark that can live in both saltwater and freshwater environments. They are found in rivers and estuaries in Australia and New Guinea, where they travel between the sea and the rivers.

Speartooth sharks can adapt to salinity changes by regulating the salt amount in their bodies. This ability allows them to find food and shelter in various habitats. The spear tooth shark is a top predator in its ecosystem, preying on fish, crustaceans, and mollusks.

These sharks play an essential role in keeping the populations of their prey animals in check. However, they are also hunted by humans for their meat and fins.

Pondicherry sharks

The Pondicherry shark is one of the rarest sharks in existence. They’ve only been observed in a few rivers in India, and their behavior and ecology are largely unknown. What we do know is that they’re incredibly elusive creatures.

Humans rarely see them, and when they are, it’s usually just a quick glance before they disappear into the depths. Because of their rarity, Pondicherry sharks are considered one of the world’s most endangered shark species.

Efforts are underway to learn more about these mysterious creatures to better protect them. However, given their extreme rarity, it may be impossible to fully understand the Pondicherry shark.

Greenland sharks

The Greenland shark is a prominent member of the requiem shark family and can grow up to 24 feet long. They are slow-moving predators, and their eyesight is poor. Instead, they rely on their sense of smell to track down their prey.

Greenland sharks are thought to live for hundreds of years and are one of the longest-lived vertebrates on Earth. Although they are not considered a threat to humans, their flesh is poisonous and should not be eaten.

The Greenland shark is intriguing, and its ability to thrive in salt and freshwater environments is genuinely remarkable.

Borneo River Shark

As its name suggests, the Borneo River Shark is found in the Kinabatangan River in Sabah, Malaysian Borneo. The Kinabatangan River is one of the longest rivers in Malaysia, and it is home to many species of animals, including the Borneo River Shark.

The Borneo River Shark is a rare type of freshwater shark; it is very shy, reclusive, and difficult to spot. The best time to see the Borneo River Shark is at night when it comes out to feed on fish.

Are there freshwater aquarium sharks?

Are there freshwater aquarium sharks?

Did you know that there are freshwater aquarium sharks? That’s right – several species of sharks can thrive in freshwater environments.

  • The most popular freshwater aquarium sharks include the Bala Shark, the Red Tail Shark, and the Iridescent Shark. These sharks are relatively peaceful and significantly add to any freshwater aquarium.
  • However, there are also some less common freshwater aquarium sharks, such as the Violet Blushing Shark, the Columbian Shark, and the Black Shark. These sharks tend to be more aggressive, so they’re not ideal for everyone.

If you’re looking for a truly unique addition to your aquarium, this might be the shark!

Can sharks live in freshwater rivers?

No, sharks cannot live in freshwater rivers because their body fluids are saltier than freshwater, resulting in them becoming dehydrated and dying.

Sharks get most of the water they need from their food. They have a specially adapted digestive system that extracts moisture from their prey’s flesh, allowing them to live in saltwater habitats. Freshwater would not provide them with enough hydration.

How long can sharks live in freshwater?

There is no definitive answer to this question because it depends on several factors, including the species of shark, the quality of the freshwater, and the shark’s overall health.

However, we know that some sharks can adapt to living in freshwater for extended periods. For example, bull sharks and the others shark we talked about early can live in freshwater rivers and lakes for days or even months at a time.

So while there is no hard and fast answer to how long sharks can live in freshwater, we do know that some species are capable of adapting to this environment and surviving for long periods.

Can great white sharks live in freshwater?

There are a few anecdotal reports of white sharks breaching into freshwater lakes and rivers, but it is unknown if they can actually survive for extended periods in freshwater environments. White sharks are generally found in coastal waters around the world, where they feed on marine mammals such as seals and dolphins.

However, these apex predators can long-distance migrations and have been known to travel thousands of miles offshore into open ocean waters.

Given their enormous variety and ability to adapt to various habitats, it’s conceivable that some white sharks occasionally enter freshwater bodies.

But whether or not they could actually survive for any length of time is another question entirely.

Several physiological adaptations allow white sharks to thrive in saltwater environments. Still, it is unknown if they could survive in fresh water for extended periods.

White sharks are ectothermic, meaning they rely on the surrounding water to regulate their body temperature. In saltwater, this is relatively easy because the ocean is a consistent temperature around the globe. However, in freshwater environments, the water temperature can vary significantly from place to place and season to season.

This could cause problems for white sharks trying to regulate their body temperature in freshwater environments.

In addition, white sharks have highly specialized kidney that helps them excrete excess salt from their bodies. This adaptation allows them to live in saltwater, but it would be useless in a freshwater environment.

Without this adaptation, white sharks would quickly dehydrate and die in freshwater environments.

So while we don’t know for sure if great white sharks can live in freshwater, it seems unlikely given their physiology.