"Coastal development threatens landscapes and eco-systems throughout New Zealand. Our coastline's natural character is being eroded by rampant development," the society said.
Te Uri chief executive Deborah Harding said a conservation trust would be established to boost resources for the protection of endangered shorebirds.
In 2002, the hapu got the land as part of a Treaty settlement and it has negotiated to sell 230ha of the forest to Mr Kayne. The statement from the two parties said the Overseas Investment Office had approved the sale, subject to certain conditions including extensive replanting and the trust's establishment to fund increased surveillance and protection for nesting shorebirds in the adjoining dunes and beach area.
The Kaynes issued a statement yesterday saying they were impressed with fellow American Julian Robertson's Cape Kidnappers and Kauri Cliffs golf resorts.
"Both those ocean-front courses rate in the top 100 in the world - a spectacular achievement for a small country - and they attract wealthy golf tourists to New Zealand with many flow-on benefits to the country," Mr Kayne said.
He said they intended to take a similar approach to Peter Cooper's Mountain Landing waterfront development in the Bay of Islands, where hundreds of thousands of native trees had been planted and wetlands restored.
Te Arai Beach plan
Between Pakiri and Mangawhai.
230ha of 616ha of Maori land sold.
LA's Ric and Suzanne Kayne new owners.
Golf course and 45 houses planned.
$5.9m being spent locally.