Cabbage Tree Island was gazetted in 1954 as John Gould Faunal Reserve. It was the first faunal reserve in NSW and was established specifically to protect the breeding site of the endangered Gould’s Petrel. Boondelbah Nature Reserve was gazetted in 1960. It is currently the site of a translocation project involving Gould’s Petrel, to assist in securing their population.
The nature reserves also provide habitat for other threatened species and migratory birds protected under international treaties, protect an area of endangered littoral rainforest, and have Aboriginal heritage values.