NARRATOR: It's a mystery.
Great whites around the world have been attacking divers
in cages, but no one knows why.
This is frightening.
NARRATOR: Finally, Dr. Greg Skomal
may have cracked the case.
He thinks the sharks are chasing bait.
They want to tease these sharks in tight to the cages,
but that shark is going to be disoriented.
NARRATOR: But there's a problem with Greg's theory.
One case doesn't add up.
What's going on here?
It's clearly ignoring that first bait,
and that first bait's actually pulled away from him.
NARRATOR: This great white seems to ignore the bait.
It goes straight for the divers.
[music playing]
You know, you've got to understand.
There's a lot of scent in the water,
so this shark is moving right around.
Let me slow things down here.
NARRATOR: But look again.
Another clue.
GREG SKOMAL (VOICEOVER): The shark goes to the back
of the cages, and there you go.
Right there.
There's a bait box behind the cage,
and the shark is checking out the bait box.
NARRATOR: This highlighted bait box is full of chum.
It sends a powerful scent to the shark.
But it's confused, it can't see the fish.
GREG SKOMAL (VOICEOVER): What's happened here
is, as it accelerates toward that box,
it realizes there's no room for it.
NARRATOR: The shark turns, but it's
too late to avoid the cage.
These are big animals.
Yeah, they're fish that are incredibly agile in the water,
but not when they're this size.
You don't want to put the baits this close to where
people are diving.
NARRATOR: There's a way to test if Greg's theory is correct--
by seeing how sharks react to cage divers
when they are drawn in by something other than baiting.
[music playing]
NARRATOR: In Australia, Marine Biologist Melissa Marquez
and boat operator Matt Waller, will attempt
to attract sharks using music.
This experiment is a real opportunity
for us to learn something new.
NARRATOR: Melissa wants to see for herself if great whites
will still attack a cage when drawn in by something
other than bait.
Good to go.
Because if there's other stimuli
such as just vibrations, and there's not food,
they might act a little bit different.
MATT WALLER (VOICEOVER): We're going to put her in the cage,
and we're going to hand her our underwater speaker.
Alright, let's start hitting the first tune.
NARRATOR: Melissa thinks music with low frequencies
best peak the interest of the sharks.
But will it also lead them to ram the cage?
What kind of frequencies are we talking around?
Forty hertz and below is a good sweet spot, I think.
You got anything headbangy?
Alright, Melissa.
"Darkest Hour" coming your way.
Get ready to rock out.
[rock music playing]
NARRATOR: A big great white comes
in not following its nose, or its eyes, but its ears.
Oh yeah.
This is more like it.
Yeah, I'm definitely picking up a little bit
interest from the shark, here.
NARRATOR: Sound travels four times faster underwater
than it does through air.
And Great whites have ears to hear it.
A small ear hole sits behind each eye.
There are able to home in on the music from more than a mile
away.
It makes sense that sharks might
be more attracted to this.
After all, they love those low frequencies.
NARRATOR: The shark comes in to check out the concert,
but shows no aggression at all.
It's evidence that no bait means no risk of a cage attack.
Acoustic attraction may offer the benefits of bait,
without the risks.
What do you think?
Are we crazy, or are actually on to something maybe
different here?
We're seeing results here, and like a lot
of things with Great White sharks,
more research has gotta be done.
[music playing]