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Language: en
Here are some facts about great white
sharks.
White sharks are live birthed, usually
in litters of between 4 and 7
individuals. Now, they're called pups,
but when they're born, they're between
1.2 and 1.5 m. So, that's a pretty big
baby.
It takes a great white shark about 10 to
12 years to reach maturity, at which
point the females are actually about a
meter longer than the males. The largest
recorded being over 6 m, roughly the
size of this red boat behind me. At this
length, they'd weigh about 2 to 3,000
kg.
Oh man. Now, there are stories of some
great whites being over 7 m, but those
are unsubstantiated.
White sharks are warmbodied. They're not
warm-blooded like us. They can't
maintain a perfectly stable temperature,
but their internal organs are kept at up
to 13° above the average temperature of
the ambient water around them. The heat
generated by their muscles is actually
transfer to the blood in their veins as
it returns from the shark's extremity,
so it warms it up and keeps the core
temperature a little bit hotter. This
allows the shark to venture into colder
waters and also to have explosive power.
Its muscles work a lot better when warm
than when cold, just like ours. The
trade-off is the shark requires about 10
times as much energy as if it didn't
heat its body. And that's why they need
to feed on these blubber rich seals and
whale carcasses.
White sharks like to hunt when it's
light out because they use their
eyesight to spot their prey. But when
they open their jaws, their eyes
actually roll back into their head to
protect them. And so they're actually
blind when they're taking a bite. Now,
they do like conditions that are a
little bit low visibility because they
rely on stealth to track down their
prey. If a seal spots them coming, it's
basically game over because a seal is so
much more maneuverable and can
definitely get away from the shark. But
they only eat sea mammals after they're
about 2.5 m long, which is why most of
the sharks we're seeing around here are
quite large. Before that, their diet
consists mainly of fish. The gestation
period is thought to be about 18 months
and that leads to a 2 to threeear
reproduction cycle. And with such small
litters, that means it takes a long time
for this shark population to recover.
There are a couple misconceptions about
great white sharks. One is that they
can't get cancer, and that's led to a
lot of people hunting them down and
trying to use their fins as an
anti-cancer soup. But in reality, sharks
get cancer just like anything else. And
there's photographic evidence of sharks
with big tumors. So, it makes no sense
to hunt down sharks as a cancer remedy
because they get cancer just like we do.
Another misconception is sharks are
coastal creatures that just cruise the
beaches waiting to bite people. In
reality, the sharks spend much of their
time way, way out at sea and very deep,
over a kilometer deep. It's kind of
shocking, but we've only found this out
in the last couple of years. So, there's
so much about sharks that remains
undiscovered. We don't know where they
go or what they do for most of the time
that they're alive. That's why research
projects like this are so important to
find out more about the shark and figure
out how we can help it rehabilitate and
and become the predator of the sea that
it once was.