 It was not until the Sydney building boom in the late 1960s and 1970s that the demand for sand resulted in the dunes becoming degraded by sand mining over much of the Kurnell peninsula.In 1967 the Reserve at Kurnell was handed over to the National Parks and Wildlife Service which, besides its environmental charter, had custody of historic sites of which Captain Cook's Landing Place at Kurnell was one.By 1974 National Parks and Wildlife Service was able to take on the full management of the Park and the Reserve Trust was disbanded.