''The abalone fishery was iconic on our part of the coast,'' says writer Tim Winton, who lives in a small town a couple of hours' drive north of Perth. ''It was a heritage thing, something we grew up eating. And now it's closed until further notice.''

For some time now, Winton has been noticing other changes in his part of the world: the endless drought, the shrinking dams, the changing flora and fauna. ''All those saving rains that you guys got in the east, we didn't get them,'' he says. ''We have been drinking the sea for four years now. Without desal, we would have been up the brown creek without any devices.''

Though Winton has in the past lent his name to select environmental initiatives, he seems constitutionally ill-suited to polemics or grandstanding; his writing is too wilful and wild to content itself with any kind of hobby horse. Yet changes of the kind that he has witnessed can't help but influence his art, the most recent flowering of which, a play titled Signs of Life, has more than a whiff of existential crisis.

Set in the central west of WA, the play features a middle-aged woman, Georgie Jutland, who is biding her time on a remote property while recovering from the recent death of her partner, Lu Fox.

Lu's unexpected departure - he fell out of an olive tree while trying to retrieve a kite - has left Georgie stranded and alone on a parched and barren farm, a used-up patch of dust whose river no longer runs. Then, late one night, Georgie hears a commotion out on the highway - car doors opening, voices, weeping. A figure emerges from the darkness: an Aboriginal man, Bender, seeks help. He says he needs petrol. His sister, Mona, is out in the car, screaming. Can Georgie help? Georgie, spooked, finally relents. But, as soon becomes apparent, what Bender and Mona really seek cannot be so easily obtained.

Georgie and Lu are, in a sense, recycled characters, having featured in Winton's 2001 novel, Dirt Music. In that book, Georgie was a bored, vodka-gulping local of White Point, a fishing village north of Perth, and Lu a Keats-quoting fisherman who gets run out of town for poaching lobsters. (Well, for that and having an affair with Georgie, who is supposedly already ''taken''.) In Signs of Life, Winton propels this couple into a dislocated and fragile future in which they must reinvent themselves or perish. Into this he adds Bender and Mona, rootless Aborigines whose need for connection is equally urgent.

''These are people in uncertain circumstances, stuck together on this property, thinking, 'Well, now what?' The land itself is shrinking, it hasn't rained for years, there's nothing left, only dogs, and even they have almost all eaten each other. So everyone is in a position of improvisation; everyone is having to put their stuff together from spare parts, bit by bit.''

Such extempore living is a familiar theme for Winton, whose entire life has been, he says, ''a form of improvisation''.

''I've never gone to work with a script, with a list of things that I have to do. I've always been one of those people who have to pull things out of their arse for a living.''

These days, of course, the strain of such a life is mitigated by his colossal success. With 10 novels and countless short stories, four Miles Franklin awards and two Booker Prize nominations, Winton is perhaps the pre-eminent Australian novelist of his generation. If Ozlit had a Mount Rushmore, Winton would be up there, his old-style whaler's face carved in stone alongside Patrick White and George Johnston. And yet, for all the accolades - National Living Treasure, Centenary Medal for services to literature - Winton is still a hippie at heart, flawed and refreshingly human.

The morning of our interview, for instance, he turns up 40 minutes late, puffing and sweaty, having run from his hotel.

''Sorry, sorry!'' he says. ''I'm like some kid - I set my alarm in a different time zone.''

Signs of Life is one of three plays Winton wrote some time ago, for reasons he can't quite put his finger on. ''I'd certainly never say I'm a playwright! The two things [novels and plays] are so different. When you're writing a novel, it has to work on the page or it isn't going to work at all, but writing for the stage you've got to make the words do more and do less: they have to do some things for the actors to allow them to get a grip on their part, and some things have to be just for the audience. Then you have to trust the actors to carry more meaning than the words alone, using their body and their experience.''

The whole thing has been ''terrifying'', he says, ''especially because I've never been a sharer''. ''Showing anything to anyone unless it's absolutely ready feels like you're airing your grubby laundry. But when you're sitting through rehearsals, you have what is normally a completely private and interior series of process and decisions, about which bits to keep or cut, with 20 other people. It's like you're sending out your dirty laundry and all these people are picking through it. It's mortifying.''

The only thing worse is actually sitting in on one of his plays. ''It's like marinating in your own shame and anxiety. I've sat on trains and planes next to someone who pulls out one of my books and they haven't made the connection that I'm there, and that can be for five hours, and you can physically register whether they are into it or not. So sitting in on a play is like sitting in a room with someone as they read this big fat book of yours, all the way through. Any time someone in the audience laughs at the gags or moans in appreciation at some sad moment, you overreact from such need and desperation that you just think, 'Can someone take me out and shoot me!'''

Even among authors, a hermetic bunch at the best of times, Winton is determinedly private. Publicity isn't his thing. He also never discloses the name or exact location of his home town. ''It's just a little cray-fishing town in the central west. There's nothing there, just 600 people and 450 dogs. It's that small that there'd be nowhere to hide once people knew. And it's great, because no one gives a toss who I am up there; I go surfing with people who don't read my books and couldn't give a rat's.''

Winton has a wife, Denise, and three children, all in their 20s. In his early career, even after his first novel, An Open Swimmer, won the 1981 Vogel Award, supporting them was a Sisyphean struggle that required juggling multiple projects. He would have a children's book, a short story and a novel on the go simultaneously, while also spearing fish and growing vegies to keep the family in food.

''I was desperate and broke,'' he told the Herald in 2008. For Christmas in 1990, Denise had to beg the bank for a loan of $150 to buy food and presents.

Cloudstreet changed all that. Published in 1991, it told the story of two working-class families struggling to rebuild their lives, and proved a huge literary and commercial success. It has sold hundreds of thousands of copies and regularly tops lists of readers' favourite Australian novels.

But unlike many of his West Australian predecessors, Winton did not follow such success by migrating east. ''I totally understand why people have been getting on trains and coming to Sydney or Melbourne, as Robert Drewe did. But I didn't want to be following the footsteps of anyone else and come [to Sydney] and make this a staging post on my way to London. That just felt so post-war - so 1950s.''

Staying put gave him ''freedom and space''. ''I was free to make myself up. You weren't in any school of writing or thought. Also, in Sydney in the 1980s, you just knew that there were books that had been contracted because of a long lunch and a bit of a leg over. For me, living in the far-left freckle of nowhere, that was never going to happen. I was going to have to make it on my own merits, or not.''

That he has indeed made it is a constant source of amazement to Winton. ''The normal trajectory is that the aristocrats pauperise themselves for their art, but I became a bourgeois by art and we are all still scratching our heads about that.

''I only ever wanted to be able to pay the rent, and I ended up with a mass readership. They don't deal many of those cards out.''

Signs of Life opens at the Sydney Opera House on November 2.