Long-suffering landowners in a controversial South Coast estate are being offered $5000 a block to hand their properties over to form part of Jervis Bay National Park.
The purchase offer has come from the Foundation for National Parks and Wildlife, a not-for-profit organisation that purchases land for conservation, which has been given $5.4 million from the federal government.
People who had bought into the estate in the 1980s and '90s on the expectation it would be rezoned to allow housing found themselves on the outer in 2009 after a decision to quarantine the area from development.
The foundation said any land it was able to purchase would be handed over for inclusion in Jervis Bay National Park, and the money being offered was not compensation, but a purchase price to protect the environment.
Foundation chief executive officer Susanna Bradshaw said the estate's 180 hectares offered an important tract of natural vegetation that allowed species to travel between Booderee National Park and other habitats.
"Developing it would have isolated the species in Booderee, making it a much less healthy habitat and ecosystem," she said.
People who respond quickly will be given an extra $500, but Heritage Estate Landowners Association president June Esposito likened it to a gun being held to the owners' heads.
"I don't see much difference to dealing with the Mafia," she said.
"At least they are offering something, but it really is an insult."
Mrs Esposito pointed out that about 1000 landowners had paid an average $20,000 for their blocks, and had since paid about $10,000 in council rates.
She said landholders would meet in coming weeks to discuss the offer, and also the possibility of a further legal challenge to the 2009 decision. Development was blocked because of the estate's environmental qualities. According to Professor of Ecology and Environmental Science at Australian National University David Lindenmayer, those ecological values have become more important over the years.
"It's a very important place for biodiversity," said Professor Lindenmayer, who has been studying Jervis Bay ecology for 10 years.
"It offers an amazing range of environments, often packed into a small area, and an incredible richness of species."
That included "the world's most important population of eastern bristlebird".
Professor Lindenmayer said parks such as Booderee were also important to the economy.
Booderee had 450,000 visitors during the previous year, more than Uluru and Kakadu combined, he said.
Ms Bradshaw said three levels of government were coming together to protect the area, with Shoalhaven City Council donating land it owns in the estate for inclusion in Jervis Bay National Park.
Shoalhaven Mayor Joanna Gash welcomed the announcement, saying it would give landowners certainty and enable them to sell their properties, at a fixed price, through a voluntary land purchase project.