For the former Director General of the NSW National Parks and Wildlife Service and senior manager in a raft of government agencies dealing with land management, this is where his journey into environmental education really took off.

"It's a nice place, and it was certainly a pretty exciting place to come to for someone like me back in 1976," Gilligan says.

Forty-four years ago, the high school science teacher was charged with helping students learn more about the natural world.

He was appointed the founding teacher in charge of the Awabakal Field Study Centre.

These days, the education centre occupies a modern building. Back then, Brian Gilligan's workplace was a rustic old schoolhouse slumbering in a gully at Dudley.

Here, through the years, thousands of students have had their eyes opened to the environment around them, as they have been encouraged to notice the tiniest details.

"It was more a case of taking in their surroundings and just being aware and being sensitive to them," he explains.

You can take the person out of the classroom, but the teacher remains in the person.

As we stroll through the reserve that was gazetted a couple of years after the field study centre was opened, Gilligan stops and picks up gumnuts, pointing out the different shapes and textures.

"That's a Grecian urn shape, and that's from the scaly bark, which is a bloodwood tree," he says.

I ask if he was always observant.

"I did like to notice things and to appreciate the little things that were around," he replies.

More than ever, Brian Gilligan is appreciating the little things. For he is on a new journey, into uncharted and challenging territory for him.

Brian Gilligan has lung cancer.

"It's a big bolt from the blue," says the non-smoker and active bushwalker.

He received the diagnosis on Christmas Eve, after visiting his GP for a check-up in preparation for a hiking holiday in Tasmania.

"A cancer diagnosis is, in one sense, a horrid thing," he says. "In another sense, it's a gift, in that you've at least got some time ahead to do some reflection."

So that's what Brian Gilligan has been doing. Only he has been reflecting not just on his own life. As well as looking inward and back, Brian Gilligan has been gazing out and forward. He's been thinking about the state of the world.

As we walk through the coastal bushland that Gilligan loves, he shares his thoughts about his health, and that of the environment. With his words, Brian Gilligan leads the way through the wilderness.

BRIAN Gilligan is a Hunter boy. He was born in 1948 and spent his early years on a farm at Dartbrook in the Upper Hunter.

He attended boarding school, but part of young Brian's education took place each holidays on the farm.

"Being able to hop on a horse and just go riding in the back paddocks was a great way of immersing yourself and getting a feel for different places, different parts of the bush," he recalls.

The landscape of his childhood has been dramatically changed, with the incursion of mining in the Upper Hunter.

Brian Gilligan has played a role in reshaping some of that land. Between 2011 and 2017, he was a state planning assessment commissioner, helping review and make determinations on major projects, including about 20 coal mine proposals.

"When I sat on the Planning Assessment Commission, we did our best to identify the issues and to deal with them as much as we could," he says.

"But we always had to make calls in the context of the law as it sits, and the government policy as it sits.

"And so we finished up having to approve things I certainly didn't feel comfortable with. But I had to satisfy myself with having to put as many practical conditions on as I could."

When asked how he feels about driving up the valley these days, Gilligan replies,

"I lament the lack of a government strategy on coal mining. The government has basically left the location and the timing of mines pretty well entirely to the market, to the private sector.

"To me, that's irresponsible."

As a young man, Gilligan worked as an exploration geologist in New Guinea and Queensland before heading into science teaching and environmental education, including at Raymond Terrace and Whitebridge high schools.

Then came the "open-ended opportunity" with the founding of the Awabakal Field Study Centre.

Brian Gilligan made the most of that opportunity.

After nine years at Dudley, he followed a network of career trails, from being a foundation director of the Shortland Wetlands Centre and on the former Hunter District Water Board to a senior manager's role with the Environment Protection Authority.

From 1998 to 2003, Gilligan headed the National Parks and Wildlife Service. He was also a member of the state's Marine Parks Authority and the NSW Heritage Council.

After retiring from the NPWS, Gilligan worked for a range of land management and environmental authorities, including the NSW Natural Resources Commission.

While his career has taken him around the world and into some of the highest offices in the land, Brian Gilligan says many of the lessons in environmental - and people - management began for him in the classroom at Dudley.

He came to realise there were some key questions to answer, including, "What's the human element of this? And how do you deal with the different values that people hold for landscape?".

"For a forester, a forest is a job. It's employment and it's bread on the table. For a naturalist or an enthusiastic bushwalker, it's a sacred space to wander through. For Aboriginal people, it's part of their very identity, it is who they are.

"So what became very clear very early is that we've all got these different perceptions, and you can either focus on identifying the common elements of those perceptions and build something that's positive and constructive and consensual, or you can focus on the differences."

In Brian Gilligan's view, the differences dominate in discussions and decision-making too often. Part of the reason, he says, is that government policy moved from being based on the work of independent public servants to being often shaped by competing interests.

"What we've got now in policy formulation is basically tribal warfare between self-interested lobbyists on one hand and very narrowly focussed activists on the other hand," he says.

"And never the twain shall meet. And we've got this division. Whereas for me, we're not a divided country, for God's sake."

One subject that divides opinion in this country is the human impact on climate change.

"It's beyond question," says Gilligan, as we stand on the shore of a lagoon.

Gilligan recalls how more than 30 years ago, he was learning about climate change from scientists, through seminars held at the University of Newcastle.

"While some of the details weren't yet clear, they've certainly become clear in the meantime," he says.

Which is why Brian Gilligan is astounded by those who argue the science on climate change is inconclusive. He believes Australia has not been contributing sufficiently to meaningful global action to deal with the issue.

"If you step back from it, the overall impression we've had of the last decade or so, at least, is that Australia has been throwing out the storm anchors, slowing and obstructing at any opportunity the global action on climate change," Gilligan argues.

"We've been told for 30 years or so, that climate change is particularly going to hit hard in Australia. If we're going to be among the hardest hit, we ought to be at the front of the pack, trying to coordinate and mobilise the global action on climate change, not at the back of the pack trying to slow the process and obstruct it for as long as we can.

"For what reason? Because some distorted economics somehow says short-term protection of a limited number of jobs in fossil fuel industries is better economically than actually tackling the problem."

When talking about where the world may be headed, Brian Gilligan thinks about the young. He is a grandfather of five.

One of the "great delights" of his life, Gilligan says, is to have conversations about these issues with his 17-year-old grandson, Mac.

"And we were talking only last weekend, and he was saying he thought the people of his generation were really good at mobilising the call to action, and mobilising the concern about the problem, but, he said, I think they need help to understand just what the options might be for what to do about it," recounts Gilligan.

"I found that really interesting, because to me that encapsulates the challenge for my generation, which is to work with the younger generation, who can mobilise and who are concerned."

As we walk amid the trees in a dry forest, we talk about the teenage environmental activist Greta Thunberg, and her famous "How dare you" speech to world leaders, as she roasted them for what she considered their lack of action on climate change.

"I can absolutely understand the frustration she feels, and where she's coming from," Gilligan says.

"Identifying the problem and decrying the lack of action. I think what is really sad is the best response some politicians and commentators have come up with is to denigrate someone like her.

"Sooner or later, that generation is going to have to sort out the mess. We can either work with them and be part of getting the mess sorted out, or we can walk away and leave it all to them, which I think would be grossly irresponsible and grossly unfair."

Brian Gilligan is doing more than talking. He is writing down his thoughts, shaping them into essays. And, at the invitation of former NSW fire commissioner Greg Mullins, he has joined the high-powered Emergency Leaders for Climate Action group, which has been urging the federal government to do more to combat growing threats, notably bushfires.

Gilligan says what he brings to the table is "a long commitment and a fair amount of experience in public land management". That includes painful experience.

He was the NPWS head in 2000, when four of his officers died and three others were injured after a hazard reduction burn at Mount Kuring-gai went wrong. One of those who died was George Fitzsimmons, the father of the current NSW Rural Fire Service Commissioner, Shane Fitzsimmons.

Gilligan has joined the Emergency Leaders for Climate Action in the midst of this summer of horrendous bushfires and the political blame game that has flared from the ashes. And he has joined after receiving the cancer diagnosis.

In part, he has signed on because of that diagnosis. Basically, Brian Gilligan wants to get on with things, to share his knowledge, and to help bridge the divide across generations, across opinions.

"To the extent to which someone who has done the range of things I've done over my time and learnt the lessons I've learnt over time, I think it is important - without getting, in any way, carried away with your own importance - to at least say, 'Some of this stuff doesn't make sense, whereas there are alternatives, and this is what some of those alternatives might look like'," he says. "So that's what I've been trying to do of late."

Gilligan doesn't think the world's climate health is "in great shape at the moment".

"I do think we have the talent, and we have the capacity, to pull it all together and get ourselves out of the hole we've gotten into," he says. "But it's going to take some time. And I think it's going to take some lateral thinking on the part of people, whether that be ancient public servants like me or our grandkids.

"But I think one hell of a lot of it is about getting those two ends of the demographic spectrum together, and just identifying the things we all value and building a consensus on the way forward."

We emerge from the trees and stand before the stunning view on the edge of the continent at Dudley Bluff.

To Brian Gilligan, this is a landscape of hope. He recalls when this area was mined just a few decades ago, with silica extracted from the sand for making glass. He points out how the environment has rejuvenated. It has changed, he says, but it looks healthy.

Brian Gilligan loves this bluff, calling it one of his "home bases".

"What I've found is you can find beauty in an awful lot of places, and you don't have to travel vast distances," he says, while gazing at the sea. "To come back to a place like Dudley Bluff just reminds you of that."

For Brian Gilligan, cancer has sharpened his focus on what he has in his life, and on what is needed in the world.

When we go for our bushwalk, Brian is in between rounds of chemotherapy, and he concedes that with this illness "the prognosis doesn't look real exciting".

Yet rather than fret about what may lie ahead, he is determined to make the most of time, to appreciate the love and support of his family and friends, and to make a difference any way he can.

Brian Gilligan is wrapping his future around that of the world.

"The interesting thing my kids, my family will all attest to is I always need a project," he says.

"So saving the world is yours?"

We laugh, before he replies, "Not necessarily that. But I was always going to be finding a project to get on with, rather than just sitting around and waiting for a final bell.

"If any of us have got any capacity, whether you've got a cancer diagnosis or you haven't, if you've got any capacity to move things in a positive direction instead of the divisive, tribal sort of way we've been dealing with things, you've got to give it a go."

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