IT WAS clear that Greens elder Bob Brown was among friends.

The cheers and standing ovation from an adoring audience said it all. Bob may be a major irritant for Australian big business and major parties in his campaign to stop logging, close coalmines, and keep the natural environment in good nick - but he's a cherished eco-warrior to his supporters.

The avid campaigner was in Murwillumbah to shore up the Federal Election bid of Greens candidate Dawn Walker in the seat of Richmond.

As it happened, Dawn didn't win the seat, but claimed 20% of first preference votes with a swing towards her of nearly 5%.

In a packed Regent Cinema, Bob outlined environmental issues and actions he was taking in response.

He said an expanding world population was consuming an unsustainable portion of natural resources. "Every day, fisheries are collapsing," he said.

"We have more mouths to feed but less land to feed them. This planet of ours is in our hands'. "Either we'll manage it through democracy or we'll fight." Bob called for a windback of "weaponry".

In his opinion, the proposed Carmichael Adani mine in Queensland - to be the biggest coalmine in the southern hemisphere - should not have been "ticked off" by the major political parties.

Coal exports should be phased out and Australia should prepare for an "age of renewable energy". Bob said the Tarkine wilderness in south-west Tasmania was "dear to his heart". "Ninety per cent of the Tarkine is still under mining exploration licence," he said.

Bob hopes to join the crew of the Sea Shepherd later this year to bring national attention to oil giant BP's plan to install a massive rig in the Great Australian Bight.

He said people had a right to protest against actions they considered wrong. "The world's been made a better place through peaceful protest," he said.

Existing protest laws have recently seen him arrested and charged.

He is currently challenging these laws in the High Court. "In New South Wales, the Baird Government has brought in these draconian laws," he said. "This cuts across basic democratic freedoms."

At the end of the night, Bob auctioned off his book, titled Optimism. "I think if I write another book, it might be called Defiance," he said.