From a submarine, Thomas Bywater takes a deeper look at the threats facing Queensland's Great Barrier Reef
Jacques Cousteau compared the wonder of the sea to a net, in which, once caught, escape is impossible.
From where I sat in my submarine, I saw no net but the exhilarating pull of the waters below was unavoidable.
"Stingray to Heron, beginning dive."
A screen of bubbles rose from the ballast tanks and boiling at the surface, disturbing what had been a serene day off the blue coral cay.
I held my breath. A pointless gesture in the diving vessel, but the anticipation was magnified in the glassy observation bubble and its uninterrupted field of view. Soon the water level rose over the hatch above our heads and the hot Queensland sun became a diffuse blue. We descended through a shoal of yellow-tailed fusilier fish, who seemed just as surprised to see us. We were diving into the Great Barrier Reef.
Barry, the mini-submarine, belongs to Aquatica — a Vancouver-based company that leases out crews and submersibles to film companies and playboy billionaires to provide views far below the water's surface.
Yet on this latest charter the submarine has dropped its fares to a modest $3170 a ride. As part of a promotion for the taxi app Uber, over the next month the team will take paying members of the public into the Barrier Reef.
This is either extremely expensive for a taxi, or very reasonable for an hour's ride in a state-of-the-art, $2m research vessel.
On the Canadian sub's previous mission to Belize, its three cramped seats were occupied by Richard Branson, and Fabian Cousteau — grandson of the famous French marine explorer.
It seems fitting then that the submarine's next port of call was to Heron Island, a small cay at the south of Australia's Great Barrier Reef and one of Jacques Cousteau's favourite dive sites.
Behind the controls was the third member of the team who had returned from the 300m dive into the Belize Blue Hole, our pilot Erika Bergman. And "pilot" seemed the right term because we were flying through the water.
The flocks of fish, and silty clouds furthered this illusion.
Just 10 minutes earlier, on the support boat above, we had been flashed a quick safety demonstration from which Air New Zealand could learn a thing or two. Succinct and to the point, instead of brace positions and the locations of life-vests we were shown how to fit a smoke hood and re-breather.
"The risk of a fire is a trillion to one," mission director Hervey Flemming assured us.
If there's a need to get back up in a hurry, the sub can ascend 60m in just 20 seconds. "It breaches the surface like a whale. It's quite something to see," he says with visible pride.
Flemming's warm enthusiasm for the project sits at odds with his dark aviator sunglasses and shaved head, which give off the aloof impression of a Bond Villain. Although that might have more to do with his chosen field of work. Having founded the Aquatica submarine team in 2013, Flemming has helped develop the fleet of Stingray submarines for any operation.
Shipping Barry from the Gulf of Mexico to Australia's east coast by plane and the back of a lorry, the size of the submarine meant it could travel below the radar for this top-secret mission.
It's called a mini-sub for a reason. About the size of a camper van, the spherical control compartment sits on two ballast tanks like skis. It's surprisingly nimble in the water too.
Back in the sub, I'm surprised to see it is being steered using a bright red PlayStation controller.
"Everything is designed for redundancy, so they're easily replaced," says Bergman, demonstrating manoeuvres on the device.
And the top speed? "Oh, about five knots."
Don't expect to cover much distance in your hour-long ride, but what it lacks in speed the craft makes up for in precision.
With the game-controller in her hands, Bergman seems deceptively young but, as chief sub pilot, she has 10 years' experience at the helm. She landed her dream role piloting the underwater vessels fresh from studies at the University of Washington's oceanography department. "It's the only job I've ever really known."
Having conducted dives throughout the Pacific and Caribbean seas, she has used her experience to raise awareness of the effect of climate change on the world's oceans. One expedition involves embarking on an all-female mission to navigate the frigid Arctic Northwest Passage, just using snorkels.
Bergman's expeditions have allowed her to see the problems of plastic pollution and melting ice shelves, first-hand.
But as we pass the coral towers of Heron Bommie — against all odds — the reef is still vibrant and full of activity.
Here in Cousteau's favourite dive site, it's easy to understand what he meant when he said: "The sea, the great unifier, is man's only hope."
A submarine ride to the coral reef may not be an everyday experience, but that's a pity. It's an amazing tool for opening more eyes to the cause.
There's life yet in the reef and life worth defending.