Next on Jonathan Bird's Blue World, Jonathan investigates
a shark feeding frenzy!
Hi, I'm Jonathan Bird and welcome to my world!
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Many people seem to think of sharks as killing machines that go crazy if a single drop of
blood touches the water. Gray reef sharks are one of the most aggressive sharks in the
world, and they travel in schools of dozens of animals.
When I dive into the water with these sharks, the splash gets their attention, and they
come over for a look.
They quickly size me up and realize that I don't look like food. Scuba divers not only
don't look like fish, but don't act like them either. The sharks soon get bored and
move on.
But what would happen if there was blood in the water? Would the sharks have a feeding
frenzy? Will they attack everything in sight?
To find out, I have traveled to Yap, an island in the middle of the Pacific Ocean, where
large numbers of Gray reef sharks patrol the reefs.
The water is crystal clear—an ideal place to perform an experiment with sharks. I can
keep my eye on them from a long way away.
The experiment begins with some leftover fish that we will use as bait. I place this bait
into a plastic crate so it will create a scent in the water, but the sharks won't be able
to reach it. Go find some sharks
Soon Captain John and I depart from the dock and make our way across the lagoon to the
outer reef, home of the gray reef sharks.
On site, I lower the ladder and we discuss our experiment.
So John... you and I are gonna go down on the bottom, we're gonna go in first right
and we're gonna wait for Mike to put the bait in. Is this the plan?
I'm working with two experienced Yapese divers who are going to help with my experiment
to find out if sharks will form a feeding frenzy if we put a lot of bait in the water.
First we prepare our dive gear, and I get suited up.
Next, John rolls into the water. He heads to the bottom and attaches a rope to a dead
section of reef, where we won't hurt the coral with the crate full of bait.
Now it's my turn to go into the water.
Mike throws the bait into the water with the rope attached, and I follow it down.
The fish are the first to figure out what's going on. They feed on the little scraps coming
out of the crate as it makes its way to the bottom.
John is pulling it down by the rope, so he doesn't need to swim with the crate among
the sharks that are lurking.
Once it hits the bottom, I move the crate to a hole in the reef with John's help.
The first part of my experiment is to see if the sharks will find the bait if they don't
see it.
It only takes about 5 seconds for the sharks to find the bait hidden in the reef.
More than 30 sharks surround me as they take turns swimming under to investigate the source
of the smell. If there is one thing that sharks can do very well, it's smell things. And
they smell dinner for sure.
The sharks can't get to the fish where it's hidden, so I move it out into the open.
I leave the wire cover on. Surely this will drive the sharks crazy and they will start
attacking the crate!
Well, not really. The sharks seem to know that they can't get at the fish, so they
just keep circling.
One bumps my camera. Probably an accident because I am too close to the bait.
Well, if that doesn't drive the sharks into a bloodthirsty feeding frenzy, maybe removing
the top of the crate will produce the expected result. I open the top and stand back. Now
the sharks are free to feed all they like.
It doesn't take long for the sharks to figure out that something has changed. I can see
their excitement level increase—they are swimming a little faster and investigating
the crate more—but they still aren't going into a feeding frenzy. They look pretty civilized
to me!
Finally one shark makes a bold move and sticks her head right into the crate for a tasty
piece of fish. Once all the other sharks see that, they start rushing in for their own
bite.
Now the sharks are getting really excited! They all want to get a piece of fish before
it's all gone. But this certainly doesn't look like a feeding frenzy to me. The sharks
are pushing and shoving each other a bit, but they aren't biting each other, and they
haven't paid me any attention at all, even though my camera is stuck practically right
next to the crate full of fish.
In all the excitement, one of the sharks grabs one of the tripod legs on my camera. Watch
it again from another angle. I'm definitely glad that is just a piece of plastic and not
my arm. But to be fair, I have the camera practically inside the crate, so the sharks
are grabbing anything that looks biteable in their competition to feed.
After all the bait is gone, the sharks return to normal almost instantly. They go back to
slowly patrolling the reef, and pretty much ignore me.
As my tank gets low on air, I swim out into the blue to get a few last shots before I
head up to shallower water to decompress below the boat.
That was incredible! So many sharks! Gray reef sharks, silvertip black tipsips, and
yet I still have all my limbs....who can explain it? Well, it just goes to show ya, sharks
are not bloodthirsty killers—they're just fish.
Later, on my second dive at the same site, we search the reef for souvenirs. As the sharks
feed, they often lose teeth in the process. Sharks have a never-ending supply of new teeth,
so when they lose a few, it's not a big deal. I find a few in the cracks below the
spot where the crate was sitting....
...and here they are. They're pretty small--they don't look like much—but they sure are
sharp.
So I tried to make a feeding frenzy, and it didn't work. I didn't get eaten alive,
and the sharks actually seemed very much in control. I proved something important.
Sharks are not stupid...they eat fish, and they have a pretty good idea what a fish looks
like. Divers are just not on the menu. Because of this, shark diving has become a safe and
popular and activity where people can get up close and personal for divers to get up
close and personal with these amazing predators
All over the world, tens of thousands of divers go diving with sharks every year. It's exceptionally
rare for anyone to be bitten. Most people find the experience not just exciting, but
interesting. Sharks are beautiful animals, and perhaps nature's most evolved predators.
Yet we can watch them from very close range without being attacked. You would not be able
to get this close to lions or bears without being in great danger. It's just another
incredible thing that can only happen in the ocean and
another reason I love the blue world!
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