The short answer to this question is, “yes whales can drown underwater”, however in order to give you a more detailed and scientific answer we need to go further in depth about how these marine mammals breathe and how it’s possible for them to drown due to their aquatic environment.

Unlike fish and other aquatic species whales are marine mammals which means they have lungs for breathing instead of gills, and because whales possess lungs they must come to the surface and breathe air in order to survive.

Fish and amphibians on the other hand are born with gills (instead of lungs) which allow them to extract oxygen directly from the water.

This difference plays a huge role in determining how fish, amphibians and marine mammals breathe.

In fact just as it’s possible for a whale to drown underwater its possible for fish to suffocate above the surface of the water because most gills are not designed for breathing air.

There are some exceptions with amphibious species as some amphibians are able to survive in both environments for an extended amount of time.

When a whale dives underwater it holds its breath just like a human or other mammal would if they were to dive underwater.

Because whales have lived in the ocean for millions of years they have adapted their lungs, vital organs and body to allow them to be more efficient swimmer and divers than most land mammals.

During deep dives some species of whale have been recorded diving underwater for up to 90 minutes before resurfacing for air.

The length of time that a whale can dive underwater for varies largely depending on the whales species as other cetaceans have been recorded taking dives for as little as 5 – 15 minutes on average before resurfacing for air.

In terms of how far a whale can dive some species of whale such as the sperm whale can dive in excess of 3,000 ft. under the waters surface while other species may prefer diving to depths of 1,000 ft. or less.

Some dolphin species such as the Amazon river dolphin may live in waters that are only a few hundred feet deep.

Another interesting characteristic of whales is that unlike land animals whales do not breathe through their mouth; instead these marine mammals breathe through their blowhole which is located on top of the whale’s head.

When you see a whale spout water from its blowhole this is a clear sign that the whale is exhaling.

The water shooting up into the air is actually caused by surrounding water on top of and around the whales blowhole being forced up by the whales powerful exhaling abilities.

Contrary to what many people think the water does not come from inside the blowhole or from water that was swallowed by the whale; it’s simply water that collected around the outside of the blowhole.

When the whale dives back underwater it contracts the muscles around its blowhole allowing it to dive underwater without worrying about taking in water because if the whale took in water through its blowhole while it were underwater it could drown.

In fact there are cases of whales that became stuck in shallow water drowning because the water was shallow enough to prevent the whale from swimming but deep enough to cover the whales blowhole and prevent it from breathing.

As for why their blowhole is located on top of their head, it is believed to be an evolutionary adaptation that was designed to make breathing more efficient and effortless.

Over the course of evolution the whales nostrils were moved from the front of its head to the top and the air passage and esophagus is separated to make hunting and breathing easier.

Having a separate hole for breathing and eating helps ensure that the whale doesn’t accidentally take in water while hunting for and swallowing its food.

In addition to holding their breath for extended periods of time whales are able to extract significantly more oxygen from the air than land animals which helps these marine mammals fill their lungs and bloodstream with clean high quality oxygen ultimately increasing the quality of each breath and allowing the whale to stay submerged for longer periods of time.

Due to the fact that these marine mammals are always surrounded by water they are always conscious of their breathing and oxygen requirements.

Even during periods of rest whales are conscious of their breathing because if they weren’t there is a good chance they would drown.

Due to their constant awareness of their breathing these marine mammals are known as conscious breathers because they are always conscious of their need for oxygen.

In order to better understand how these marine mammals survive in the water electroencephalographs have been attached to a dolphins head in order to observe what goes on when it is resting.

Studies have shown that when a dolphin is resting half of its brain remains conscious in case the dolphin needs to come up for air or make a quick escape from a predator.

This mental process and respiratory control also exists among the whale species.

In fact whales, dolphins and porpoises are all marine mammals belonging to the cetacean family, and they all share many of the same physiological characteristics with one another.

Aside from being similar in terms of respiratory control and the way their mind works these marine mammals share a number of other common traits that can be found in almost all mammalian species such as: