WHEN men were going to the moon, Sylvia Earle was leading the first team of female aquanauts to the bottom of the ocean, where they stayed for two weeks in a small laboratory.
The expedition - the first of nine times she has lived underwater - was a ''transformative'' experience for the marine biologist. ''I got to know individual fish. I saw where they slept, who they hung out with,'' she recalled yesterday.
Dubbed 'Her Deepness' by the US media, Dr Earle had gone on her first expedition in a submersible two years earlier, in 1968, when she was four months pregnant.
She felt perfectly at ease. ''The only danger about going down in these subs is you get hooked.''
In 1979, she wandered, untethered, almost 400 metres below the surface in an astronaut-like atmospheric diving suit.
And in 1986, she set a depth record, diving solo to 1000 metres in a submersible.
''It looked like a little sports car that you drove around under the water.''
Lonely? Never, as she documented the uncharted terrain. ''There were all kinds of creatures out there to keep me company,'' she said.
A former chief scientist of the US National Oceanic and Atmospheric Administration, and an explorer-in-residence with National Geographic, her motto is still ''ever onwards and downwards''.
At 76, after more than 7000 hours spent underwater, she still regularly plunges to the blue depths. ''As long as I breathe, I expect to dive.''
But she devotes much of her time to arguing for better protection of the world's oceans, from mining, overfishing, bottom trawling and pollution.
In an address at the Sydney Institute of Marine Science on Monday night, she said that organisms in the ocean make most of the oxygen that humans breathe. ''We need to take care of the systems that keep us alive. There is no green if we don't take care of the blue.''
Yet only slightly more than 1 per cent of the world's oceans were protected, she said. Today, Dr Earle, who was brought here by the Pew Environment Group, will be in Canberra to address a parliamentary forum ahead of federal government decisions on protection of two marine regions: the south west of Australia and the Coral Sea. She said Australia had an historic opportunity to increase its marine reserves and protect the unique marine life.
''It is something that benefits everyone … forever,'' she said.
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The story Her Deepness drops in and warns of growing threat to the oceans first appeared on Fairfax Regional Pages.