Australia's natural heritage includes lands that are reserved in parks and other places, both listed and unlisted. Although the ongoing addition of examples of the full range of ecosystems within each of the 85 bioregions to the National Reserve System is important, broader considerations such as conservation of geological sites, ecosystems and habitats and a national whole-of-landscape approach to natural heritage protection will foster values-based management and build resilience. Environmental conditions across the continent are highly variable, so selection of places for listing or reservation should consider individual place values as well as wider landscapes and ecosystems. Major barriers to a genuinely representative reserve system include scarce remnants of some ecosystems, the economic value of land that can be used for other purposes and political will. The current National Reserve System target of 10% is commendable (but yet to be achieved), but there are strong arguments that a greater sample of the natural environment should fall within reserved protected lands or be recognised as heritage, irrespective of tenure.
Habitat loss and invasive species represent major and continuing threats to natural heritage values. The landscape is changing metaphorically and literally. The outlook for habitats will depend on a combination of natural adaptive management and thoughtful intervention—the latter is highly dependent on proactive research and cooperation between scientists and managers. The situation is mixed in relation to invasive species. Some, like mimosa and cane toads, are well beyond eradication and can only be continually managed. Others, like myrtle rust and Phytophthera could respond to well-resourced eradication programs.
Natural heritage resources are also subject to continuing threats from a variety of external factors. These include inappropriate development on adjacent lands, impacts from over-visitation or inappropriate visitor behaviour, inadequate expertise and technical skills, and the perpetual problem of insufficient resources relative to expectations for managing land with natural heritage values. One potentially useful approach to this resourcing question is to place greater value on the ecosystem services of reserved lands and their role in carbon sequestration, water catchments and benefits to society (see Chapter 8: Biodiversity).