Truly brave people accept that they may not see victory in their own lifetime. You just keep at it for the sake of those who come after you. You might not win but you stand a better chance by doing something.

We rise to a challenge and set a course. We take a decision. You put your mind to something. Just deciding to do it gets you halfway there. Daring to try.

I grew up in a whaling town. We didn't stop whaling in Australia until 1978. And I've always lived in fishing communities. You could say I'm from the Redneck Wing of marine conservation. Everything I know about the sea I learnt at the end of a spear or a hook. Seems weird to admit it, but I hunted and killed my way to enlightenment. Eventually you see where you've been. All the traces you leave are gaps and absences. And it's a sick feeling, knowing you might bequeath a full dose of Nothing to those who come after you.

People do change - individuals, families, nations - and the pace of transformation need not be geological.

The ocean is a supreme metaphor for change. I expect the unexpected but am never fully prepared.

There is nowhere else I'd rather be, nothing else I would prefer to be doing. I am at the beach looking west with the continent behind me as the sun tracks down to the sea. I have my bearings.

Australia was once a leader in taking global warming seriously. The former PM [Kevin Rudd] called it 'greatest moral challenge of our time'. But in the past couple of years the national consensus has been eroded and Australians are being encouraged by the polluters and their mates in Parliament to forget it was ever mentioned. It's heartbreaking.