Dr. Bob Harrison, a motivational speaker, once said: “A shark in a fish tank will grow 8 inches, but in the ocean, it will grow to 8 feet or more. The shark will never outgrow its environment and the same is true about you.”
But is this true?
Sharks outgrow their tanks if held in captivity, but they do not outgrow their environment. Sharks are natural travelers with quick speeds and hardly stay in one place for too long. A shark’s environment, though, depends on the species.
Where Do Sharks Live?
To understand how sharks may or may not outgrow their environment, it is good to discuss where sharks live.
These deep sea creatures are versatile and some can even live in both saltwater and freshwater.
Saltwater sharks live throughout the ocean. These sharks are best adapted for saltwater and travel constantly.
Some sharks live close to the coast, while others prefer deep waters with an abundance of space.
The majority of the world is covered by the ocean, meaning you can find saltwater fish in the arctic under the ice as well as colorful coral reefs.
Examples of saltwater sharks include hammerheads, great white sharks, whale shakes, and more!
Interestingly, bull sharks can interact with saltwater and freshwater, but in saltwater, they live close to the coast of the Gulf of Mexico.
There are a lot fewer freshwater sharks, including bull sharks, Speartooth sharks, Ganges sharks, and the Borneo River sharks.
Aside from bull sharks, the rest are very rare and hard to find. They live in warm and brackish waters, mainly in Asia. For example, the Ganges shark commonly swims in rivers in India.
Interestingly, the Ganges shark looks almost identical to the bull shark, but their teeth are not as sharp.
The Borneo River shark is the rarest river shark in the world. It only grows 2 feet long and does not outgrow its environment, staying in the Kinabatangan River.
Do Sharks Have A ‘Home’?
Unlike other fish, sharks do not have a ‘home’, but a general area they enjoy. For instance, bull sharks will stay in warm waters, but they travel throughout the world even into rivers.
Sharks are constantly on the move. They need to swim to breathe. These large predatory fish have a huge diet of fish, squid, lobsters, smaller mammals, and even birds resting on the surface of the water.
They are not tied down to one location. Sometimes, sharks come together to hunt for food in groups, but it is rare.
Great White sharks do not have a home but return to similar areas to feast on large schools of fish. Hundreds of Great White sharks reach the same spot each year in April as tagged by scientists.
It is a good thing sharks do not have a ‘home’. Anything can threaten their species, including overfishing. When there is a lack of food in the area, sharks continue traveling until they find an area with more.
Can A Shark Live In A Tank?
Some sharks can live in large tanks, but they require space. Although there is a quote stating that sharks stop growing in captivity, this is not true and not all species are built for tanks.
There is a decline in the health of sharks living in captivity. With less space to swim, these sharks only live up to nine years.
A lot of aquariums also keep sharks in tanks. The first shark in an aquarium tank was in the 1860s. Science has come so far that now aquarium lovers can take care of a shark as a pet.
If you are an aspiring aquarium hobbyist and want to own a shark, start with a small species like the Bala shark. These sharks thrive with other fish of the same size or larger.
Sharks Living In Captivity
Large sharks, like the Great White shark, do not do well in captivity. In fact, no Great White sharks are living in captivity. Most Great White sharks that were caught in an aquarium did not live past one day.
Most larger animals need a lot of space. They do not have a home and will outgrow their environment if they don’t have the space to travel for food.
Great White sharks feel immense stress when they are away from home. One was caught in Japan. The 11.5-foot shark continued ramming its head onto the wall until it died.
During the shark’s stay at Japan’s Okinawa Churaumi Aquarium, it also refused to eat.
In 2004, the Monterey Bay Aquarium in California captured a female Great White shark that survived 198 days before release. The shark killed two other sharks in the same tank before the aquarium released it.
Only four years after the most successful attempt at keeping a white shark in captivity, a fisherman caught two baby great white sharks and placed them in a restaurant tank. In 17 hours, both were dead.
All in all, sharks are not picky about their environment. There is no such thing as ‘outgrowing’ their environment in the wild since they travel quickly by swimming.
Sharks claim the ocean as their entire home, as long as the water conditions are right!