"The biology of tiger sharks, Galeocerdo cuvier, in Shark Bay, Western Australia: sex ratio, size distribution, diet, and seasonal changes in catch rates." Environmental Biology of Fishes. Scientists say that predators such as the tiger shark keep the ocean's ecosystem in balance, and in Native Hawaiian belief, tiger sharks are aumakua, or sacred guardian spirits. However, not everyone is out to get the tiger sharks. Because of these human threats - tiger sharks have no other predators in the sea - tiger sharks are listed as a near-threatened species by the World Conservation Union. As we learned in the last section, this might not be an effective way to catch the offending animal because tiger sharks don't usually stay in the same place for long. In Hawaii in the late 1950s, after a spate of tiger shark attacks, a state-sponsored program provided $300,000 to rid the waters of tigers. Tiger sharks are also among the sharks caught for sport by fishermen, and sometimes the government has sponsored the fishing of tiger sharks. Tiger sharks also are harvested for their flesh, which can be used to make leather, and for their livers, which have high levels of vitamin A and can be used to make vitamin oils. Fishermen eager to cash in on the high price of shark fins sometimes amputate the fins of sharks and then release them, which is a death sentence because definned sharks cannot swim fast enough to catch their prey. In Hong Kong, a tureen of shark-fin soup costs $100. Shark fins provide the spaghetti-like noodles in shark-fin soup. Tiger sharks have also been known to eat other tiger sharks, but they're not the only ones - a tiger shark's fins are a hot culinary commodity in Asian culture. In Hawaii, for example, the odds of being attacked by a shark are about one in 5 million. Together, these three sharks are responsible for 99 percent of attacks on humans, but these numbers shouldn't necessarily keep you out of the water. According to the International Shark Attack File, the tiger shark has been responsible for 155 attacks on people since 1580, far behind the great white's 437 and edging out the bull shark's 110. Because the tiger shark's appetite is so voracious, it's also less likely that they'll just try a nibble and retreat, as some other sharks do. īecause tiger sharks live in warm waters, they're likely to make human contact, and sometimes people become the prey of the tiger shark. Scientists are still determining whether such a diet means that the tiger shark is primitive and unevolved in its willingness to eat anything, or whether being able to eat anything is a smart evolutionary defense.
Rubber boots, bags of charcoal, boat cushions, hubcaps, pets, raincoats, handbags, cow's hooves, deer antlers, lobsters, a suit of armor, sneakers with legs attached…this list could go on for a while. But what gets people's attention is the wackier things that have shown up in a tiger shark's stomach.
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