Wait so California state granted $24 million to the private Wildlands Conservancy, who spent $35 million for the property. California should have just bought the property and turned it into a state park. This should be public land.
This is a well-known concern in land preservation. There's apparently an offshore island near Maine that's too small and too far out to be of much use to humans, but it's an important migratory bird resting point.
IIRC, it was donated to the state once by conservationists (long ago), sold by the state, and then repurchased and preserved by a non-profit foundation. The state won't be getting it again!
The usual approach in the US is for the land conservation foundations to split up the ownership rights between two different local organizations in a way that prevents developing the land without agreement from both organizations.
As a general rule, most towns are happy with this setup. It provides them with public walking trails, and possibly areas for other outdoor sports. Many towns choose not to tax these lands, within reason.
As long as the general rule of law is strong with robust property rights, however, creating a new private organization like a trust with a strict charter that limits its future stakeholders is a lot easier.
Hell, look at monasteries. Several societies with large religious followings couldn't prevent the dissolution of monasteries - Tang Dynasty China (cutting down Buddhist ones), and Tudor England (cutting down Christian monasteries).
What a clever approach!
Is it possible to instead write something in the terms of the donation preventing this? Maybe that would require larger action from the state, like a state congressional vote though.
I haven't dug deep and the organisation probably has ton of issues, like parasites attached to a host, but the general picture I got is that the public trusts it.
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Humans never evolved to coordinate as a society. Our natural course: the most psychopathic humans ruin the environment and the masses of "good" humans don't look / react because they don't have a sense of urgency. Philip K. Dick's story Project Earth tells about Project C (Earth being Project B), a species designed to solve this.
These sorts of public/private land trusts are by far the most popular way in California of ensuring wildlands are not developed and remain open for public access. It makes sense for the state to contribute to them, too, because they provide QoS guarantees - and financing largely supported through philanthropy - the state would never be able to ensure.