Sharks are marine predators that live and are well adapted to life in the ocean. They have exceptional senses which allow them to detect the movement of their prey from great distances.
But how do they operate under the ocean, do they need oxygen? If so, can sharks drown?
Yes, sharks certainly can drown. Although they breathe differently from us humans and marine mammals, sharks can drown for a lot of different reasons.
Let’s take a closer look…
Can Sharks Actually Drown?
It is certainly possible for sharks to drown in the ocean. Sharks rely on their gills to extract oxygen from the water so that they can breathe.
If for whatever reason, their environment has a shortage of oxygen, the shark is no longer able to extract oxygen from the water and will drown.
Although it may seem a little bizarre at first, it can happen due to different natural and man-made causes and is more common than you may think.
Humans are incredibly intrusive when it comes to marine life, and they can often contribute to the reason why sharks drown.
How Can Sharks Drown?
There are a variety of reasons why sharks can drown, but here are a few that are most common.
Being Pulled Backwards
Although it’s incredibly rare for a shark to be pulled backward in the water, and usually only happens when being caught on fishing like on a trawler, it can make the shark drown.
Sharks need to keep moving forwards in order to breathe as water passes by its gills and can extract oxygen.
If a shark is pulled backward, this can alter its breathing pattern and cause the shark to suffocate/drown.
Shark Finning
Shark finning is the act of hunting sharks for their fins to sell in countries where shark fin soup is a delicacy.
This act has caused so many killings of sharks, both legally and illegally.
Shark fin soup in countries like China is seen as a symbol of status and has both a high monetary value as well as a cultural value too.
In Chinese culture, emperors would offer their guests shark fin soup as it is thought to have medicinal benefits.
However, the act of shark finning is what makes sharks drown in the ocean. Fishermen catch sharks, cut off their fins and then throw them back into the ocean.
Sharks rely on their fins for movement, so losing one is the same as losing an arm or a leg for us humans.
This can mean some sharks are so badly damaged that they are unable to move and sink to the bottom of the ocean and drown.
Shark finning is incredibly damaging to the shark population, with species like the hammerhead being in trouble of extinction.
Being Upside Down
If a shark is turned upside down, it can induce a paralyzed state known as “tonic immobility”, also known as “animal hypnosis”.
Scientists have explored this phenomenon to try to learn more about sharks’ behavior, with sharks being able to be essentially paralyzed for up to 15 minutes whilst in the state.
However, if left in this hypnotic state for long enough, the sharks can drown as they are unable to receive oxygen from the water.
Some incredibly intelligent animals have capitalized on this, such as the Orca. Off the coast of California, an eye-witnessed reported seeing an Orca purposely turn a great white shark onto its back to induce this state.
After a period of 15 minutes, the Orca kept the shark upside down which resulted in death and a quick meal for the Orca.
This has now been reported in a number of cases, with the Orca catching on that if they hold sharks upside down they will drown.
How Do Sharks Breathe In Water?
Like fish, sharks have gills that allow them to extract oxygen from the water in order to breathe. It’s a pretty handy tool for life under the water, meaning unlike marine mammals, they don’t need to surface for air.
Sharks have evolved over millions of years, to the point where some species of apex predators dominate the oceans.
Whilst swimming, this allows some sharks to help keep oxygen-rich water flowing over their gills ensuring that they can breathe.
During this process sharks allow water to flow through their mouths and over their gills.
Inside their gills, they have a filament, which contains thousands of blood vessels that help absorb oxygen from the water.
Excess water flows out of the shark from their gill slits, giving them the oxygen they need and allowing the excess to flow out of their body easily.
It was believed at one point in time that because of this method of extracting oxygen from the water, all sharks must stay on the move to survive.
However, this belief did not take into account the many species of shark that do not swim at all, like the Nurse Shark, and it’s now known that not all sharks need to move to survive.
What Happens If A Shark Stops Swimming?
Most sharks switch between a combination of buccal pumping and ram ventilation whilst swimming to extract oxygen.
However, some species of sharks have lost their buccal pumping ability and will drown if they stop forcing water over their gills.
There are actually only around 20 or so sharks that are required to stay on the move for survival, these include the Great White Shark, Mako Shark, and Whale Shark.
For the most part, many species of sharks will be fine if they stop swimming, as they have evolved to use both methods of forcing water through their gills to survive.
Final Thoughts
So, can sharks drown? Absolutely. There are a number of reasons why a shark may drown as set out above, with the most common being shark finning.
This is a sad reality that sharks have to face in the wild, they are caught to have their fins removed and are often thrown back into the water where they will be eaten by larger predators or drown, with few surviving.
Many species of sharks have now evolved to the point where they do not need to stay in constant motion to survive.
However, there are still some species that must, often the largest predatory sharks need to stay on the move, which is why very little is known about their sleeping habits.
Thanks for taking the time to read this post and I hope you’ve learned something new today about how sharks drown.
Feel free to stick around to learn more about sharks and other interesting marine life.
Hi, I’m George – the founder of MarinePatch. I created this blog as marine wildlife has been my passion for many years. I’ve spent over a decade in the marine wildlife industry and spent years out in the field conducting research. In today’s modern world, an online blog is the best place for me to share my findings and reach as many people as possible to help educate and inspire others. Enjoy your time here and you’re welcome back anytime!