I personally find individual efforts to save the planet by fencing off bits - 'just for the animals' a bit weird and a bit scary. The Dancing Star Foundation is based in California and was set up by the late Sue Stiles.
The DSF website says
The refuge is not open to the public but is the sole domain of the wild biodiversity that dwells therein, watched over by dedicated staff members. Along with Ulva Island, this will be the only predator free piece of land on all of Stewart Island/Rakiura, and the first true place of safety for native species in 150 years on the Stewart Island mainland, New Zealand's third largest island.
Below is a short video by DSF CEO Michael Charles Tobias setting out the DSF vision.