A new assessment by IUCN, released during the 2025 IUCN World Conservation Congress, reveals deepening risks to natural World Heritage sites from climate change, invasive alien species, and emerging pathogens.

The IUCN World Heritage Outlook 4 shows that 43% of natural World Heritage sites now face a “high” threat level from climate change – surpassing any other threat globally. Invasive species remain the second most widespread pressure, affecting 30% of all sites, while pathogen threats have surged: 9% of sites are now considered at high or very high risk from disease, compared to just 2% in 2020.

Complementing the official monitoring processes under the World Heritage Convention, the World Heritage Outlook provides an in-depth analysis of threats facing natural World Heritage sites globally, as well as their protection and management status.

Over the past decade, the proportion of sites with a positive conservation outlook has declined – from 62% in 2020 to 57% in 2025. Only half of assessed sites are considered to have effective protection and management measures in place, and one in seven face significant risks due to funding deficits.

Yet several properties have shown improvement, driven by effective governance, inclusive management involving Indigenous Peoples and local communities, and long-term partnerships that strengthen ecological resilience. These include four sites in West and Central Africa – Dja Faunal Reserve (Cameroon), Salonga National Park, Garamba National Park (Democratic Republic of the Congo), and Niokolo-Koba National Park (Senegal) – all of which have improved their conservation outlook. Their progress reflects the impact of targeted financial assistance, including from the World Heritage Fund supported by Norway and other partners, combined with strengthened site management and collaboration among conservation agencies.

Leveraging World Heritage for the Global Biodiversity Framework

During the Congress (8–15 October 2025, Abu Dhabi), IUCN – the advisory body to the World Heritage Committee on natural heritage – in cooperation with UNESCO convened a series of thematic sessions dedicated to World Heritage.

One event, co-organized by UNESCO and IUCN with the International Indigenous Peoples’ Forum on World Heritage and the World Commission on Protected Areas, examined how the World Heritage Convention can be harnessed to advance the Kunming–Montreal Global Biodiversity Framework (GBF). Discussions emphasized the importance of aligning the Convention with the rights-based approaches to conservation promoted by the GBF and demonstrated how its global visibility and standards can contribute directly to GBF targets on effective conservation, connectivity, and equitable governance.

Delegates also highlighted opportunities for both natural and cultural World Heritage sites to advance biodiversity conservation, as well as the potential of the World Heritage Convention to mobilize additional financial resources to support these efforts. During discussions, a proposal was put forward to establish a dedicated funding stream for World Heritage within the Global Environment Facility (GEF), aiming to strengthen the Convention’s contribution to the Global Biodiversity Framework and ensure sustained, site-level conservation action.

These discussions build on the expert report endorsed by the World Heritage Committee earlier this year, which identifies 19 priority actions to strengthen synergies between the Convention and the GBF.

“No-go” commitments and corporate accountability

A dialogue on World Heritage “no-go commitments” brought together representatives from the corporate sector, including the International Council on Mining and Metals (ICMM), TotalEnergies, and the World Bank, to reaffirm that extractive and other large-scale industrial activities are incompatible with the Outstanding Universal Value of World Heritage sites. Participants shared examples of how businesses can lead in setting industry standards that align with global heritage protection commitments.

The discussion recalled findings from the UNESCO-led study Extractive Activities in UNESCO World Heritage Sites: Commitments, Risks and Investment Implications, which found that 36% of natural World Heritage sites overlap with existing or planned oil, gas, or mining concessions. The report urges full implementation of “no-go” commitments and provides guidance for investors and companies to integrate World Heritage safeguards into decision-making. 

Tools for more effective management

Several sessions showcased IUCN conservation tools that support World Heritage implementation. The IUCN Green List of Protected and Conserved Areas was presented as a model for effective governance and management that helps sites achieve measurable conservation success.

In parallel, an event on Multiple Internationally Designated Areas (MIDAs), organized by the UNESCO Category 2 Centre Global Research and Training Centre for Internationally Designated Areas (GCIDA), examined how World Heritage sites overlapping with other international designations – such as Biosphere Reserves, UNESCO Global Geoparks, and Ramsar Sites – can help address threats beyond site boundaries and strengthen cooperation, governance, and monitoring. At the same time, overlaps can pose challenges due to differing legal frameworks, governance structures, and limited understanding of their impacts. The discussions highlighted recent advancements to support integrated management, such as the UNESCO Sites Navigator, and the potential of better coordination, with updated guidance for MIDAs expected in 2026.

Joint effort to protect our shared World Heritage

The 2025 IUCN Congress reaffirmed that the World Heritage Convention is not just a recognition mechanism, but a strategic tool for advancing the Global Biodiversity Framework (GBF), climate resilience, and sustainable development. As the world nears the GBF’s midpoint, the findings of IUCN World Heritage Outlook 4 and discussions at the Congress highlight the need for renewed collective action – from strengthening site-level management and coordination across overlapping designations, to mobilizing resources, enforcing “no-go” commitments, and promoting inclusive, rights-based approaches involving Indigenous Peoples and local communities. Together, these efforts demonstrate how the Convention’s global mandate can be translated into tangible outcomes on the ground, securing these irreplaceable places for future generations.