When food passes from the mouth to the stomach, it is stored in this last portion and thus begins the process of digestion. If the shark feels that ingested any bad food, it is not digested by the stomach, and then it is expelled through the mouth. Some Shark species will eat huge meals and then not eat again for weeks. They can survive on the oil that is stored in the liver when they do eat. When that gets low, they will have the instinct to eat again.
As you can see, sharks eat a variety of foods. While most of them are meat eaters, that is not the only thing they eat. For millions of years, the various species of sharks have been able to evolve. One reason for this is that they have eaten what is readily available as necessary to stay healthy and to be able to reproduce successfully.
The amount of food that a shark eats each day depends on the type of shark it is. Posted in:. Email this page to a friend. In average, the peregrine shark filters every hour about 2 million liters of water from which it obtains only 2 kilograms of plankton. Their teeth are tiny, although present; they do not use it in the feeding process.
Strictly all sharks are carnivores to some degree. And although it sounds incredible, they only consume 0. The digestive system of sharks is very different from that of mammals, and this is the reason for their slow digestion.
They have a spiral valve inside a short section, and their intestines are very short. When food passes from the mouth to the stomach, it is stored in this last portion and thus begins the process of digestion. If the shark feels that ingested any bad food, it is not digested by the stomach, and then it is expelled through the mouth. Some Shark species will eat huge meals and then not eat again for weeks. They can survive on the oil that is stored in the liver when they do eat. When that gets low, they will have the instinct to eat again.
As you can see, sharks eat a variety of foods. While most of them are meat eaters, that is not the only thing they eat. For millions of years, the various species of sharks have been able to evolve. One reason for this is that they have eaten what is readily available as necessary to stay healthy and to be able to reproduce successfully.
Different sharks have specialized teeth tailored to their preferred prey. Great whites have razor-sharp, triangular fangs to slice through the thicker, fattier flesh of larger fish and sea mammals.
Since tiger sharks enjoy crustaceans, their teeth resemble steak knives with serrated edges and a rounded shape to break through the shells.
Filter feeders like whale sharks have row upon row of short, blunt teeth since they don't have to rip through anything [source: Parker ]. But despite sharks' reputation for voracious appetites, they may be the target of something else's mealtime cravings. Find out on the next page when sharks become prey. In the food hierarchy of the sea, large sharks often swim at the top.
However, even the fierce great white sharks have enemies in the water. Killer whales that weigh around 5 tons 4, kilograms have eaten great whites before [source: Cawardine].
Crocodiles , seals and other sharks may also prey on younger sharks. By far, sharks' most threatening predator is humans. Shark meat has become increasingly popular as food , and manufacturers also use shark cartilage in some medicines. In , the United States exported 4, tons of shark and dogfish meat [source: National Marine Fisheries Service ].
Although the United States imported 32 tons of shark fin in , it, along with Canada, New Zealand, Australia and South Africa, has banned the fishing tactic of catching sharks, slicing off their fins and tossing them back in the water [source: National Marine Fisheries Service ]. Because of the success of commercial shark fishing and the problems with catching sharks as a byproduct of other fishing ventures, certain species populations have dwindled recently.
Some shark experts have estimated that the overall number of sharks in the water has dropped as much as 90 percent [source: Kelly ]. They also fear the decline because sharks reproduce at a much slower rate than other fish because most species carry their pups like mammals.
At the same time, commercial shark fishing advocates argue that the business profits fishermen and also protects people from deadly shark attacks. In reality, the widespread concern about shark attacks is overblown in relation to the incidence rate. People die each year from gruesome shark-related injuries, but only 30 of the nearly species have ever made contact with humans [source: Florida Museum of Natural History ]. Of those 30 or so species, shark specialists consider around a dozen as potentially harmful to people.
Because of the higher concentration of muscle in humans' bodies, sharks will sometimes take a bite and release a victim since they prefer fattier foods [source: Klimely ]. Sign up for our Newsletter! Mobile Newsletter banner close.
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