Whales, unlike fish, breathe air. That’s why whales can come up to the surface of the ocean when they need some oxygen because all whales actually have lungs.
Whales cannot live in freshwater. However, they can exist in saline seas. This love of saltwater may be attributed to the minerals present in freshwater or because whales are, in fact, marine animals and require more sodium than land-based humans.
Can whales survive in freshwater?
In short, no. Like other marine mammals, whales are specially adapted to life in the ocean. In fact, they need salt water to survive.
If a whale lives in freshwater for too long, it will eventually die. Some species of river dolphin have been known to live in freshwater for extended periods but not without great effort and stress.
In general, whales have a very specialized diet. It is thought that baleen whales (like humpbacks) eat krill and plankton, which only grow in the ocean.
Toothed whales (like orcas) eat fish, squid, octopus, and other marine mammals. The vast majority of species live their entire lives in saltwater.
Since whales live such a long time (some species may live for over 70 years), they have to adapt their life history to the availability of food and water in their environment.
Whales do not drink salt water because they would then absorb too much saltwater, which would be toxic to their bodies. Instead, they get all the freshwater they need from the food they eat.
The salt content of the ocean is critical to whales for other reasons as well. They have adapted sonar systems that involve bouncing high-frequency sound waves off of objects in the water.
These sound waves are reflected back towards the whale if they hit something large enough (like another animal or a fishing boat). The salt in the water helps whales to hear more clearly by giving the sound waves something to reflect off of.
Whales are also buoyant in saltwater.
Since their bodies are denser than the water they live in, most whales will sink like a rock if dropped into fresh or even salty water. Most whale species would not swim if placed in freshwater because they cannot keep themselves afloat.
In some cases, a few species of freshwater dolphins have adapted to living most or all of the time in freshwater rivers and lakes. These animals can survive for extended periods out of the water, but they never wholly lose their ability to live in saltwater.
Even though it is impossible, whales could undoubtedly survive in fresh or brackish water for a while.
This would be especially true of baleen whales which are much more flexible in their diet than toothed whales. They might be able to catch fish out of freshwater rivers and eat plankton from the surface of freshwater lakes. However, these creatures need saltwater to survive in the long run.
Whales are amazing creatures, and it is difficult for us to imagine what life would be like if they did not exist.
They provide food for hundreds of thousands of other ocean-dwelling organisms, and their active role in the community helps keep everything in balance.
Can whales die if they go into freshwater?
It’s not common, but it has definitely happened before. While whales are partially adapted to living in saltwater environments, they can die if they fall entirely into freshwater. They need a brackish climate to keep their skin healthy and prevent infection.
The worst-case scenario for a whale that has fallen into freshwater is that it dies of dehydration and starvation.
The whale will be stuck in the freshwater because its internal salt concentrations and balance have been disrupted, and it can’t survive there long enough to adapt or return to seawater.
How do whales get freshwater?
Whales get freshwater from the food they eat. When a whale eats, saltwater gets filtered out of its mouth through the baleen and is expelled as waste.
The freshwater stays in the whale and is absorbed through the lining of its intestines.
If a whale drinks fresh water while it’s in the ocean, it will get sick and possibly die because it needs the salt in its body to balance out the ocean water.
Most whales will only drink fresh water when they are in a river or other body of freshwater.
Why do whales swim up rivers?
Whales travel to diverse seas to find food and feed their young, and their offspring survive. Some whales may be drawn to salty water.
On the other hand, others will go as far upriver from the ocean’s edge as freshwater becomes accessible before returning with food supplies at harvest time.
Because the estuaries are shallower, they are more appealing to fish and other animals that feed on young offspring still developing within these circumstances.