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Here are some facts about great white sharks: white sharks are live-birthed, usually in
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litters of between four and seven individuals.
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Now they're called pups, but when they're born they're between 1.2 and 1.5 meters!
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So that's a pretty big baby.
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It takes a great white shark about ten to twelve years to reach maturity at which point
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the females are actually about a meter longer than the males - the largest recorded being
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over six meters - roughly the size of this red boat behind me.
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At this length they'd weigh about two to three thousand kilograms.
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Oh man!
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Now there are stories of some great whites being over seven meters but those are unsubstantiated.
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White sharks are warm bodied.
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They're not warm-blooded like us - they can't maintain a perfectly stable temperature, but
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their internal organs are kept at up to thirteen degrees above the average temperature of the
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ambient water around them.
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The heat generated by their muscles is actually transferred to the blood in their veins as
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it returns from the shark's extremities, so it warms it up and keeps the core temperature
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a little bit hotter.
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This allows the shark to venture into colder waters and also to have explosive power.
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Its muscles work a lot better when warm than when cold, just like ours.
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The tradeoff is the shark requires about ten times as much energy as if it didn't heat
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its body and that's why they need to feed on these blubber-rich seals and whale carcasses.
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White sharks like to hunt when it's light out because they use their eyesight to spot
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their prey.
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But when they open their jaws, their eyes actually roll back into their head to protect
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them and so they're actually blind when they're taking a bite.
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Now they do like conditions that are a little low visibility because they rely on stealth
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to track down their prey.
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If a seal spots them coming, it's basically game over because the seal is so much more
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maneuverable and it can definitely get away from the shark.
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But they only eat sea mammals after they're about 2.5 meters long, which is why most of
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the sharks we're seeing around here are quite large.
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Before that, they're diet consists mainly of fish.
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The gestation period is thought to be about eighteen months and that leads to a two to
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three year reproduction cycle and with such small litters that means it takes a long time
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for this shark population to recover.
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There are a couple misconceptions about great white sharks.
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One is that they can't get cancer and that's led to a lot of people hunting them down and
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trying to use their fins as an anti-cancer soup.
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But in reality sharks get cancer just like anything else and there is photographic evidence
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of sharks with big tumors so it makes no sense to hunt down sharks as a cancer remedy because
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they get cancer just like we do.
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Another misconception is sharks are coastal creatures that just cruise the beaches waiting
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to bite people.
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In reality the sharks spend much of their time way, way out at sea and very deep, over
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a kilometer deep.
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It's kind of shocking but we've only found this out in the last couple of years so there
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is so much about sharks that remains undiscovered.
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We don't know where they go or what they do for most of the time that they're alive.
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That's why research projects like this are so important to find out more about the shark
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and figure out how we can help it rehabilitate and become the predator of the sea that it
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once was.