Why Are White Shark Attacks on the Rise? | SharkFest


NARRATOR: Great whites are the most
feared predator in the ocean.
They typically hunt large mammals, like seals,
sea lions, and whales.
But they are also responsible for more attacks on humans
than any other shark species.
And that’s not all.
When Collier digs into the details from the other four
incidents in 2014, it appears they were all
carried out by white sharks.
So what’s making the great whites of Southern California
suddenly go on the attack?
Good morning.
Thanks.
NARRATOR: According to shark expert Dr. Andrew Nosal,
a great white’s actions are highly
driven by the presence of prey.
And a major food source for these predators
can be found along the coast here in abundance.
DR. ANDREW NOSAL: There’s a seal.
NARRATOR: Pinnipeds.
A great white’s favorite food are pinnipeds,
like the California sea lions we see behind us.
And they like them because they’re full of fat and full
of nutrients.
NARRATOR: But there may be a particular time
when sharks need to gorge themselves on these pinnipeds–
right before they make an incredible annual journey
to a remote and mysterious location
nicknamed the White Shark Cafe.
DR. ANDREW NOSAL: The White Shark
Cafe is located about halfway between California and Hawaii–
so right about here in the middle of the open ocean.
NARRATOR: Dubbed a pool of nothing,
this unremarkable patch of sea is
roughly the size of Colorado.
And for some reason, every year great whites that typically
swim solo gather here by the hundreds
as part of the largest known congregation
of white sharks in the world.
It’s unclear what the purpose of the White Shark Cafe is.
But one theory is that this is a place where
mating is actually happening.
NARRATOR: Not only that, but these predators
remain here in the middle of nowhere for months.
DR. ANDREW NOSAL: We typically see the white sharks leaving
California about November, December,
and then late summer is when we see them start showing up again
off the coast of California.
NARRATOR: But this long-term stay seems odd because there
appears to be a distinct lack of one crucial thing at the cafe–
food.
DR. ANDREW NOSAL: For a long time,
we thought that it was a desert of sorts.
There was nothing there.
NARRATOR: So if there’s nothing to eat when they arrive,
could great whites be stocking up
on pinnipeds before the journey in order to sustain themselves?
DR. ANDREW NOSAL: White sharks want the easy meal,
so they’re going to go to a place
where there’s a lot of seals and sea lions.
NARRATOR: A place like the California coast.
So are humans here simply in the middle of a feeding frenzy?
Is that what’s causing this alarming spike in attacks?
According to Nosal, the answer lies far below the surface
of the cafe where, in 2018, scientists
make an unexpected finding involving the very thing
that appeared to be absent–
food.
[uplifting music]
DR. ANDREW NOSAL: Turns out that there’s
actually a lot living there.
There’s all kinds of fish and crabs and things in the water
there.
NARRATOR: This prey just lives much
deeper than could previously be seen on satellite images.
DR. ANDREW NOSAL: So because they’re feeding there,
I don’t think the white shark stocking up on food right
before their migration is a sound explanation
for the uptick in shark bites.
[dramatic music]
NARRATOR: Something else must be driving great whites to attack.
And maybe it isn’t what they’re hunting,
but what’s hunting them.

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