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Why aquariums can’t hold great white sharks When you go to the aquarium, you see a lot of sharks. You’ll find Horn sharks, Leopard sharks, and Cat sharks, but there’s one shark that aquariums aren’t able to hold, and that’s the Great White (C.carcharias). With the great white being the largest predatory fish, it attracts huge crowds. There were many situations of aquariums like Marineland, SeaWorld and the Steinhart Aquarium, that have attempted to hold the Great white (C.carcharias) in captivity, but none have been successful. They either died or they were set free due to the shark's behavior. The reason why you see certain sharks rather than great whites (C.carcharias) in aquariums, is because they have big differences. One example of a shark you see in the aquarium is the Horn Shark (Heterodontus francisci). They can grow up to four feet. They normally swim towards the bottom near reefs, sandy areas and rocky bottoms. Their diet consists of sea urchins, crabs, and shrimp. Horn Sharks (H. francisci) are considered little threat to humans because of their size and teeth structure. You will also see a Leopard shark (Triakis semifasciata). They can grow up to seven feet. They also swim towards the bottom above the sand. Their diet consists of clams and fish eggs. But, as Leopard sharks get older, they start to eat fish. The leopard shark (T. semifasciata) isn’t known as danger to humans. The International Shark Attack File states that there is only one incident of a leopard shark (T. semifasciata) with a human. But, the Leopard shark (T. semifasciata) didn’t leave any significant damage to the victim involved. The Catshark (Scyliorhinidae) can grow up to three feet. They swim towards sandy, coralline, algal, gravel and muddy bottoms. Their diet consists of mollusks, polychaete worms, and gobies. The catshark (Scyliorhinidae) is considered harmless to humans because of its size, habitat preference, and feeding habits. Nurse sharks (Ginglymostoma cirratum) can grow up to seven feet. They swim towards lagoons, sandy areas in close proximity to reefs, and off sandy beaches. Their diet

consists of cephalopods, sea urchins, surgeonfish. The nurse shark (G. cirratum) is known as docile, so it has a few non-fatal attacks on humans attributed to this species. All of these sharks are similar in a way. Their sizes don’t make them known as predatory sharks. They all don’t swim in open ocean because they are mostly found swimming towards the bottom. They also don’t eat large fish. When you compare the characteristics of a great white shark (Carcharodon carcharias) to common aquarium sharks, you’ll see why they hold the title of, “top predator throughout world's ocean.” The great white (C.carcharias) has very good senses. Their most accurate sense is smell because their olfactory bulb is the largest of any shark. Although sharks ears are hard to see, there are cells that can sense even the tiniest vibration in the surrounding water. Great whites (C.carcharias) also have good vision. Their retina is divided into two areas, one for day and one for night. They protect themselves by rolling its eye backward into the socket when threatened. They also have an elaborate sense of touch from their lateral line. They can detect the direction and amount of movement made by prey, as far as 820 feet away. These go to show why they are the ocean’s top predators/hunters. The great white shark (C.carcharias) can grow up to twenty-two feet. And unlike common aquarium sharks, they migrate long distances. It’s said that great whites can travel from Hawaii all the way to California. They stay in the epipelagic zone, which is the surface layer of the ocean. Great whites (C.carcharias) diets depend on season, area, and age. They hunt seals, sea lions, fish, squid, and even other sharks. They are known to have more fatal attacks on humans than any other species of shark. It’s due primarily on its size, power and feeding behavior. Because the great white (C.carcharias) is the largest predatory fish, aquariums throughout the 1970s to 1990s repeatedly tried to hold great white sharks in captivity. It attracted

huge crowds, but, unfortunately, none of them were successful. The sharks either died because they weren’t swimming or eating, or were set free because of their behavior. For example, there was an issue where the great white would eat other sharks in its tank. The aquarium that held a great white (C.carcharias) for the longest period of time is the Monterey Bay Aquarium. It was said that it took the aquarium a lot of effort, and nobody has done it since. They held a great white shark for six months. Because of this, their attendance increased by thirty percent. The strategy that they used to keep the shark alive for so long is that they designed a million gallon, egg-shaped tank, that was thirty-five feet deep. It was specifically designed for open-ocean animals. Instead of taking in a big shark, they took a small shark that was the size of four feet and four inches, which is less than a year old. The reason why the aquarium no longer held the shark is because it had killed two other sharks. It takes a lot of work to transport great white sharks (C.carcharias). When the Monterey Bay Aquarium got a hold of the baby white shark, instead of taking the shark straight to the aquarium, they set up a four million gallon pen in the ocean. The reason behind this was, they wanted the shark to eat before putting it in a transport tank that would travel from southern california, all the way to the aquarium. The trip was known to be a nine to eleven hours. In order for the Monterey Bay Aquarium to transport the shark, oxygen sensors, video cameras, lighting, and filtration systems were needed to transport one baby great white shark. Since the average shark size is fifteen feet, it was very difficult for aquariums to build a tank for them. There are some sharks, like Nurse, angel, and lemon sharks, that have strong enough neck muscles to circulate water even while the shark is resting. In order for Great white sharks (C.carcharias) to get oxygen, they need to move forward with their mouths open so that water can pass through their gills. If the shark doesn’t move forward, it will eventually weaken. That’s why they weaken

when they are caught in a net. If they are caught in a net, they aren’t able to swim through, eventually leading to them drowning. This shows as another reason why the aquarium needed certain transport equipment. The great white shark (C.carcharias) swims long distances. Sean Van Sommeran, who is part of the Pelagic Shark Research Foundation, snuck into the Monterey Bay Aquarium with photographers, and took pictures of the great white sharks. They viewed that the sharks had visual sores from bumping into the tanks. It’s easy to recreate habitats for sharks that live near reefs. But, it’s hard to recreate habitats for pelagic sharks because they like swimming long distances in the open ocean, rather than just circling in one place. Great whites (C.carcharias) are also used to swimming long distances without hitting anything. So, they aren’t good with walls. They repeatedly run into the glass, causing them to injure and stress themselves. The monterey bay aquarium said that this was the issue with their sixth great white shark in 2011. They decided to set it free after being in the aquarium for only fifty five days.

Works Cited “8 Things You Should Know About Sharks Now That Shark Week Is Over.” Medill News Service, 9 Aug. 2017, dc.medill.northwestern.edu/blog/2017/08/09/shark-facts-youshould-know-post-shark-week/.

“Carcharodon Carcharias.” Carcharodon Carcharias :: Florida Museum of Natural History, www.floridamuseum.ufl.edu/fish/discover/species-profiles/carcharodoncarcharias/. “Heterodontus Francisci.” Heterodontus Francisci :: Florida Museum of Natural History, www.floridamuseum.ufl.edu/fish/discover/species-profiles/heterodontus-francisci/. “Nebrius Ferrugineus.” Nebrius Ferrugineus :: Florida Museum of Natural History, www.floridamuseum.ufl.edu/fish/discover/species-profiles/nebrius-ferrugineus/. “Scyliorhinus Canicula.” Scyliorhinus Canicula :: Florida Museum of Natural History, www.floridamuseum.ufl.edu/fish/discover/species-profiles/scyliorhinus-canicula. Team, Smithsonian Ocean. “Great White Shark.” Ocean Portal | Smithsonian, Smithsonian's National Museum of Natural History, 31 Aug. 2016, ocean.si.edu/greatwhite-shark. “Triakis Semifasciata.” Triakis Semifasciata :: Florida Museum of Natural History, www.floridamuseum.ufl.edu/fish/discover/species-profiles/triakis-semifasciata/. “Why No Aquarium Has a Great White Shark.” Eventbeat, 8 July 2016, eventbeat.org/why-no-aquarium-has-a-great-white-shark/....