Next on Jonathan Bird's Blue World,
weird sharks that live on the ocean floor!
Hi, I'm Jonathan Bird and welcome to my world!
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This is a fearsome predator. It looks like a blob, or perhaps an algae-covered rock.
But it's a shark, blending into the sea floor, waiting for small fish to come within
striking range. The shark is called a Wobbegong, and I have come all the way to Australia to
find this unusual fish.
It's a beautiful morning in the Gold Coast region of southern Queensland, Australia,
and Palm Beach Dive center is putting their boat in the water.
I load my gear while the crew prepares scuba tanks.
The divemaster is my good friend Glen Holmes who grew up here. I met him ten years ago
in the Caribbean, and he promised that if I flew all the way to Australia, he would
show me some very cool Wobbegongs. So here I am!
We pull away from the dock and head out to sea.
We're heading out to a dive site called Julian Rocks in search of Wobbegongs. Captain
Herb is driving the boat and we have about hour to get there.
We arrive at a small desolate island—barely more than a rock--and start getting ready.
Glenn has been diving here for 20 years and he knows where the sharks are. I suit up and
prepare myself for chilly water!
Well, lets go see if we can find a Wobbegong!
I go over the side and follow Glenn as we search for Wobbegongs.
This region is right at the edge of the tropics, so there isn't much coral. The bottom is
covered mostly in seaweed and rocks.
Under an overhang I find my first Wobbegong shark. It's a big Ornate Wobbegong, almost
as long as me!
Wobbegong sharks have adapted to live camouflaged on the bottom, rarely moving a muscle until
a meal-sized fish comes into range. It's called an ambush predator because it waits
for the prey to come within striking range and then lunges for it, rather than trying
to chase prey around. If any of those fish above its head get too close,
they will get gulped down!
Nearby, A Spotted Wobbegong tries to get comfortable. Even though there are millions of tiny silver
fish swarming above its head, this Wobbegong isn't feeding. It's stuffed. Every Wobbegong
here has been gorging itself for days. They can barely move.
Moving out into deeper water, I find several Sand Tiger sharks, often called Grey Nurse
sharks in Australia. These sharks look and act a lot more like a typical shark.
They let me get pretty close for some pictures.
Not too long ago, people thought all sharks had to keep swimming like the sand tiger,
to keep water moving over their gills.
For some species, like the hammerhead, this is true. Hammerheads must keep swimming at
all times or they'll drown. They never rest on the bottom.
But many species of sharks sometimes stop swimming and rest on the bottom. Here a Lemon
shark is taking a break on the sand, gulping water through its mouth to ventilate its gills.
Here's a pair of Nurse sharks, common in the Caribbean, also resting on the sand. They're
not in the mood to socialize. As I approach, they swim off.
Wobbegongs on the other hand, spend their entire lives on the bottom, patiently waiting
for prey. They very rarely swim because it gives away their position.
Although there are more than 400 species of sharks, you might be surprised to learn that
a huge number of them look nothing like the typical predator most of us associate with
sharks, like these Caribbean reef sharks.
Of course, the Wobbegong look nothing like a reef shark.
In 2006, a new species of bottom-dwelling shark was discovered in Indonesia. It belongs
to a group of sharks called epaulette sharks. What made this one different is the fact that
it actually walks along the bottom on its fins, so they called it the Walking shark.
Cameraman Pierre and I charter a traditional Indonesian Pinisi and set off to a remote
region of Indonesia to find this elusive shark!
As the sun sets, we board the inflatable boat and head to the dive site.
I've come to a remote reef in Papua, Indonesia, to find a really weird shark!
The walking shark is usually only found at night. So Pierre and I search the reef in
the dark after sunset.
It takes a while, but we find the little shark. It doesn't like our lights at all, and getting
any decent shots of it proves difficult. But you can see how it walks on its fins!
Not exactly a fearsome predator. This little shark hides from us in the reef.
The next day, I suit up and roll off the inflatable boat again. This time we're searching the
reef for another Wobbegong.
The most common Wobbegong on Indonesian reefs is called the tasseled Wobbegong. Its tassels
located around the edge of its head allow it to blend in to the bottom really well by
disguising its shape.
On a typical reef, this shark blends right in!
It's very confident in its camouflage and won't move, even if I get really close.
The Wobbegong has a clever way of breathing. Instead of gulping water in through its mouth,
it has a set of spiracles, almost like nostrils, right in front of the gills. Water goes in
through the spiracles, and then back out through the gills. It's an adaptation for a shark
that spends a lot of time flat on the bottom.
So sharks are a diverse group of animals, and they don't all look the same.
The walking shark and Wobbegong
are all examples of the amazing kinds of bottom-dwelling sharks.
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