Reporter: Liam Bartlett
Producers: Jonathan Harley Lincoln Howes and Garry McNab
If you think white pointers are big, wait till you see this shark.
It's the size of a bus, the biggest, most majestic fish in the sea. No wonder they call it the whale shark.
And we can tell you, up close it looks pretty scary.
Fortunately for Liam Bartlett, though, this particular monster from the deep is harmless, one of those gentle giants.
And that's been it's downfall. That and the fact it's considered a delicacy in Asia. But now there's a new, unexpected threat.
It's become a huge tourist drawcard. A major attraction for super aquariums around the world.
And, tragically, for the whale shark, that attraction can be fatal.
LIAM BARTLETT: When you're about to go swimming with the world's biggest sharks off Western Australia's Ningaloo Reef, there's one simple instruction:
BRAD NORMAN: They're comfortable with us swimming in the water. As long as we don't impede their path, you'll have a great experience.
LIAM BARTLETT: And they only eat plankton, right?
BRAD NORMAN: Yeah, yeah. You'll be safe.
LIAM BARTLETT: Beautiful, beautiful okay, let's do it.
BRAD NORMAN: Here it comes let's move to the side. Come this side.
LIAM BARTLETT: How can you tell it's coming? How can you tell it's coming?
BRAD NORMAN: Look under the water, you'll see it.
LIAM BARTLETT: And there it is … a sight nothing can prepare you for. I'm eye to eye with seven metres of whale shark, and a few friends hitching a ride. To my surprise, I'm anything but scared. This is one of nature's great privileges, and mysteries, because we just don't know that much about them. What we do know is they're the biggest fish in the world, quietly cruising the oceans, feeding on plankton. Whale sharks can live for 150 years and grow up to 18 metres long, and they've been around forever.
DR MARK MEEKIN: These things haven't changed for about 60 million years since the age of the dinosaur. I mean, walking with dinosaurs forget it you can swim with one here, now. It's an incredible thought. This is a satellite tag. It's a, um, incredible piece of technology really. It records temperature, light and depth over a 6-month period.
LIAM BARTLETT: Dr Mark Meekin is one of Australia's leading marine biologists. He is going to use this high-tech tag to add one more piece to the whale shark puzzle. So they're quite large, aren't they? But, I, mean compared to the whale shark I suppose that's that's tiny?
DR MARK MEEKIN: Well, it's a bit like leaving your mobile phone on a bus, isn't it? It's going to tell us where it's been but, in terms of the whale shark, it's a pretty small encumbrance, I think. Mark's done this countless times before but, even for him, it's no sure bet. On the first attempt, the tag won't go in and, not surprisingly, the whale shark's not happy and disappears into the safety of the deep. This is bad news because they can dive down to 1,500 metres. It looks like we've lost him. There's a few anxious moments but, incredibly, the whale shark returns to the surface and we get a second stab at it. How was that?
DR MARK MEEKIN: Perfect.
LIAM BARTLETT: Yeah, it looked very accurate.
DR MARK MEEKIN: That was exactly where I wanted it so you don't get a better shot than that that's perfect.
LIAM BARTLETT: Well, let's hope we learn something from it.
DR MARK MEEKIN: We'll get a bunch of different things. We'll get the position of the shark and it's track along the surface of the ocean, we'll get water temperature, and we'll get depth. So we'll find out something not just where it's going but what it's doing while it's there.
LIAM BARTLETT: It's here that our exhilarating story is about to make you angry. Mark Meekin's tag could also end up showing what other people are doing to whale sharks, and it's definitely not scientific research. From western India to southern China, fishermen have hunted the whale shark to the point of oblivion.
DR MARK MEEKIN: There's a taste for whale shark right through ethnic Chinese communities throughout South-East Asia. Cooks up to about the consistency of tofu and they call it 'tofu fish' for that reason. It's also the fins the fins are extremely valuable for their shark-fin soup trade.
LIAM BARTLETT: How would you describethe health of the numbers at the moment?
DR MARK MEEKIN: Look, it's a worry at the moment the health of the numbers at the moment. Virtually any place around the world that has been tracking whale sharks has shown a decline. Swimming with a whale shark leaves a big impression on you. You know, you get this thing coming out of the gloom at you and it resolves itself into this incredible shark-shape animal with the dots and the stripes all over it on the dark-blue background they're a beautiful animal. Yeah, you know, the thought of eating it, ah, does strike you as something that's pretty abhorrent.
LIAM BARTLETT: And I've got to agree. It's heartbreaking to imagine killing, and then eating, one of these magnificent creatures, and that's not the only terrible fate awaiting them. Gee, that is a blast. Tell you what, though when you see those gentle giants in this magnificent, pristine habitat, just swimming with them, it leaves you absolutely dumbfounded to think that somebody could take them out of this and put them into a man-made tank.
WOMAN: They weigh between 250 and 650 pounds. But that's what's happening. Whale sharks have become the must-have exhibit for aquariums around the world. This one, in Atlanta, Georgia, has not just one, but four, of the big fish. This aquarium is huge. They proudly tell me it's bigger than 10 Olympic swimming pools. But it's not the Indian Ocean. And he'll just come up here, will he?
KEEPER: That's exactly right. He knows it's time for breakfast, so you'll see him cruising by here any second.
LIAM BARTLETT: Meal-time is rather curious and a little bit sad. This is hardly as Mother Nature intended, but scientists here maintain these whale sharks are as healthy as those at Ningaloo Reef.
KEEPER: Last bit come back.
RAY DAVIS: It is possible to maintain a wide variety of ocean voyagers within an aquarium setting very successfully.
LIAM BARTLETT: Ray Davis is the aquarium's senior marine scientist.
RAY DAVIS: What we're seeing in behaviour and growth - these animals are doing very well in this environment. The two females have grown to nearly 20-feet long since their arrival, so it's quite astonishing to see that growth on any animal.
LIAM BARTLETT: But not all whale sharks thrive in captivity. Put simply, these big fish don't do well in small ponds. Two have already died here this year. On average, whale sharks in aquariums rarely survive more than three years. Extraordinary, considering they can live for up to 150 years in the ocean. If you've got state-of-the-art facilities and you've only got a 50 percent success rate do you still reject the notion that it's not good to keep these things in captivity?
RAY DAVIS: I would say that it's too early to say they do not do well in captivity.
LIAM BARTLETT: But surely it's better to stay alive in the wild than die in an aquarium?
RAY DAVIS: But they also die in the wild and, as we see with other zoological settings, we are able to complete a life cycle, we're able to have animals born, live, go through their cycle and die.
LIAM BARTLETT: Albeit a much shorter one?
RAY DAVIS: No, not necessarily.
LIAM BARTLETT: But certainly in the case of the two that died this year?
RAY DAVIS: The two that died this year is still under investigation.
LIAM BARTLETT: Just looking at them through that window, what goes through your mind?
PAUL WATSON: I just see, you know, dead whales swimming really, because they're going to die. Their lifespan is going to be drastically curtailed because of this captivity.
LIAM BARTLETT: For the last 30 years, eco-warrior Paul Watson has been waging war against Japanese whaling. Now, he's fighting for whale sharks. He says putting them in tiny tanks and claiming it's good for education and research is bunkum, and he's more than happy to point it out to Ray Davis.
PAUL WATSON: What you're doing is you're doing lethal research. It is really no different than the Japanese doing lethal research in Antarctica by killing whales. I mean, you're doing lethal research because these whales will die.
RAY DAVIS: What you have is the ability to look at the physiology and growth of these animals in this setting, and apply that understanding.
PAUL WATSON: But it all can be done in the wild. It is being done in the wild.
RAY DAVIS: I'm sorry. It is not being done in the wild.
PAUL WATSON: The greatest impact is on the sharks. People might learn they die. There must be other ways of learning without having to kill the animals.
RAY DAVIS: And we're not. What we have ...
PAUL WATSON: You already have. You already have.
LIAM BARTLETT: Gentleman, look at this. Look at the size of that. They dive to 1500 metres in the wild. This tank is 10 metres deep. How can that not be cruel?
RAY DAVIS: We take a look in understanding why do they dive deep we have other animals that occur deep or move throughout a water column as well as migratory.
LIAM BARTLETT: Well, what does that mean, 'Move through a water column'. What does that mean? This thing dives up to 1500m in the wild. This is 10m deep.
PAUL WATSON: And it swims for thousands of miles.
RAY DAVIS: It's been demonstrated that animals that we see ranging widely do very well in zoos and aquarium settings.
LIAM BARTLETT: An aquarium in Atlanta is a long way from the splendour of Ningaloo Reef, and I know where I'd rather be. My guide, marine scientist Brad Norman, and I have barely left land when, out of the blue, a pod of humpback whales appear. It's just that, that old word 'majestic' springs to mind. It's absolutely magnificent, isn't it?
BRAD NORMAN: And nobody gets sick of seeing whales, I mean - You've got whales here, you've got whale sharks, you've got dugongs, so, ah, it's a bit of a marine playground, that's for sure.
LIAM BARTLETT: But we can't hang around watching humpbacks because our eyes in the sky have spotted another whale shark ...
PILOT: Two miles on you, 12 o'clock, heading west.
LIAM BARTLETT: … and I'm getting another chance to swim with these gentle giants. Every year, 7000 tourists are lucky enough to see this ocean wonderland. Brad Norman wants everyone who swims with whale sharks to take photographs, not just for their holiday albums, but for scientific research. He says it's another key to understanding more about them and their movements around the oceans of the world.
BRAD NORMAN: As we build up this level of knowledge on their migration it is going to help us understand the species better and ultimately help with their conservation. See how the shark has got all spots all over it? Slightly different to the real shark, but still got lots of spots they're like a fingerprint.
LIAM BARTLETT: There's no doubt this is the best aquarium of all and perfectly combines the classroom with conservation. And the great part is a threatened species has a real chance to prosper in the place they belong.
DR MARK MEEKIN: They are truly the perfect animal for their environment. Over all that time they've managed to actually get the shape and their habits to such a point that it perfectly fits with their environment. And you've swum with one, you've seen it go past. It looks like it fits there.