From activism to "not-quite-government": the role of government and non-government actors in the expansion of the Australian protected area estate since 1990

What can we learn from the prodigious expansion of the non-government protected areas that now comprise 12% of terrestrial Australia? An increasingly professional, formal, and diverse non-government sector has developed since 1990, comprising private individuals, non-government organizations, and First Nations and having close ties to governments. We investigate the drivers, dynamics, and diversity of this sector through thematic analysis of 24 key informant interviews and associated gray literature. Changing environmental movements, science-led conservation, partial recognition of First Nations land rights, international agreements, and neoliberal reforms combined to formalize the sector during the 1990s. A bipartisan policy framework for incorporating non-government lands in the national conservation estate, diverse partnerships, transnational networks, and innovation in public and private funding helped grow the sector. The confluence of interests that has transformed the politics and practice of nature conservation in Australia is likely to inform those engaged with similar changes elsewhere.