The risk increases as off-shore pollution increases and as more people eat more fish including shark.

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Larger fish such as shark, king mackerel, swordfish, and tilefish tend to be highest in mercury because they eat smaller fish and consume the mercury in them as well.

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Levels of mercury in fish other than shark, swordfish and marlin did not give cause for concern.

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"You might as well ask a great white shark to be nice to fish or a fox to go vegetarian, " he argues in the film.

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This diet was supplemented with fresh fish caught as they traveled, including tuna and shark.

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Any prey lurking below, typically a small fish called Mueller's pearlside, will not see the shark coming.

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At a spring festival gathering in February, the Hong Kong Pui Ching Alumni Association ordered a 10-course meal but opted to replace the shark's fin soup with a chicken, fish belly and abalone soup.

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Like many of the most palate-challenging delicacies, it gets its distinctive flavor (think rotten fish meets stinky cheese) from aggressive fermentation, which takes place during the six weeks or more the shark carcass spends buried underground.

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