That the trees were protected 20 years ago in a national park, along with its 200-metre high dunes, owes much to an intervention of The Nature Conservancy (TNC), the world's largest environmental NGO by revenue. The group bought and then handed over land to help secure the park. It retains ownership of a neighbouring ranch while it works out how best to nurture a sustainable bison herd and preserve the region's other wildlife. A bison roams on land purchased by The Nature Conservancy in the San Luis Valley of Colorado. Credit:Tony Jupp "We're joined at the hip - the TNC and parks," Mr Bunch said, adding TNC is typically much more nimble than the federal agency. "The TNC is like the racing car, parks are like a semi-truck," he adds. "They can also be political - that's something we can't be."

Growing globally Loading The US-based organisation has the wherewithal to sway both sides of politics, boasting chapters in all 50 states with Democrats and Republicans well represented on all its trustee boards. Globally, they also count more than a million members, including about 30,000 in Australia - which is one of 72 nations they work in. Since 1951, TNC has used its philanthropic heft with annual revenues now approaching A$2 billion to save "parcels of paradise", often selling or gifting them to governments when they are ready to manage the conservation work. All up, it has helped protect almost 50 million hectares - or twice the size of Victoria.

Earlier this year, they made their biggest splash in Australia, teaming up with a farm investment group to secure the largest purchase of private land for conservation in the country's history. The $55 million purchase will protect the Great Cumbung Swamp, near the junction of the Lachlan and Murrumbidgee rivers in NSW, while keeping some grazing and opening up ecotourism. Another purchase in northern Australia is nearing completion. The Great Cumbung Swamp was part of a property purchased by The Nature Conservancy and its partners in 2019. Credit:David Banks Unrelated to the purchase - but an indication of TNC's ambition - is its "balanced water fund". It claims the vehicle is a world-first, using its returns to meet conservation, Indigenous, farming and investment targets. "The best time to water wetlands is when they are wet, and the best time to water crops is when they are dry," says Rich Gilmore, TNC's Australian head, about how the fund is managing its water entitlements even through the drought.

Philanthropic muscle Richard Kingsford, a leading ecologist at the University of NSW, said he admires the transparency of TNC and the can-do approach of its almost 4000 employees - including about 500 scientists. "Conservationists talk a lot. They get on and do stuff," Mr Kingsford said. "They are also very good at getting the philanthropy muscle into conservation, which is very important as government appetite for this wanes. "It's what you expect from exploiters rather than protectors. You've got to roll up your sleeves and protect what needs to be protected." Many Australian environmental workers - ranging from Indigenous teams to private and public ones - have also benefited from TNC's training schemes.

The Great Cumbung is home to 131 bird species and more than 200 plant species. Tim Beshara, federal policy director for The Wilderness Society, said the coaching he received about eight years ago has helped shape his work. "It was really useful," Mr Beshara said. "They've got a level of professionalism we don't have here, where we have to scramble just to survive." #MeToo mishaps Perhaps befitting an organisation run at its top by former corporate and government high-flyers, the TNC has faced its share of management turmoil.

Lately, a #MeToo type scandal has rocked the organisation, with outside lawyers called into examine sexual harassment claims against then president Brian McPeek. While the claims turned out to be "utterly, totally false", TNC decided Mr McPeek had to step down, Tom Tierney, the chairman of its global board, told the Herald this month. The inquiry, though, revealed other issues, including an undisclosed relationship between the head of its North American operations and the head of global programs, both of whom had to go. Mark Tercek, its chief executive who had been planning to leave after a decade at the helm, also announced his exit earlier this month. Mark Tercek, the out-going chief executive of The Nature Conservancy, at a volunteer summit in Washington DC in June 2019.

"Four out of the top eight have gone," Hugh Possingham, an Australian ecologist who heads TNC's science programs, said. "That's a lot of head-rolling." Sally Jewell, the former Obama administration Interior secretary, will take on the role of interim chief executive as the TNC addresses the probe's finding that some women believed it was difficult to thrive at the organisation and that their complaints about misbehaviour had gone unheeded. 'Nightmare'

Mr Tercek said "the whole nine-week thing has just been, for me, a nightmare". "I worked for 25 years at Goldman Sachs. I loved that. But this is more demanding."