There are several reasons why dolphins can’t live on land.
First, dolphins require a steady supply of fish and other aquatic species to survive.
In some cases, dolphins may dive up to 700 ft. or more to find specific food that their body is used to and easily digest.
If dolphins lived on land, they would not find the types of food they need to survive.
If they could find food, there is no guarantee that their body would be able to process the food.
Instead, there is a good chance that their digestive system would not be familiar with it and may not be able to digest it properly, leaving the dolphin malnourished and starving.
Secondly, dolphins need to stay hydrated to survive.
Anyone who has seen a beached dolphin or beached whale knows how important it is for them to always be in the water.
Most beached dolphins can only survive on land for a short time (a few hours) before becoming dehydrated, especially in warm or hot climates.
Third, dolphins do not have the limbs necessary to walk on land and thus become immobile.
Again beached dolphins often end up stuck on the sand and cannot return to the ocean because they are incapable of walking on land or, like a beached dolphin, back to the sea.
Fourth, while this may not apply to all species, some dolphins, such as the killer whale, are extremely heavy.
After a few minutes of being on land, a large dolphin may have difficulty breathing due to its massive size.
In water, dolphins are provided with buoyancy and do not have to worry about their weight the way humans do.
However, once they are on land, gravity has the same effect on them as on all land animals.
Dolphins live exclusively in the ocean because they have not developed the necessary muscles to sustain themselves on land.
Reasons Dolphins Can’t Live on Land:
- Dehydration
- Heat
- Immobility
- A lack of food
- Difficulty breathing
What About Their Ancestors?
Interestingly, the earliest ancestors of whales and dolphins did live, hunt, and survive on land.
They also had limbs used for walking (bones can still be seen in the flipper of cetaceans), and their spine appears to have been designed for traveling on land as opposed to in the ocean.
It explains why dolphins arch their backs and flukes when they swim instead of moving from left to right like fish.
Then there’s the fact that whales, dolphins, and porpoises are all mammals, breathe air and give birth to live young despite living exclusively in the ocean.
Again this is very different from fish that are mainly cold-blooded, breathe through gills and lay eggs.
Throughout millions of years, cetaceans slowly evolved and took to the ocean to adapt and survive.
Their limbs became flippers and flukes, their nostrils moved to the top of their head (now known as blowholes), and they developed a thick layer of blubber to help them survive in the coldest climates.
These evolutionary changes took many millenniums and eventually evolved these mammals into the ocean-bearing creatures we know today.
For dolphins to evolve and walk on land, it would require millions of years of slow evolution and a steady habitat to survive.