Interpretation and limitations

The World Database on Protected Areas is the most comprehensive global database on protected areas. However, it is neither complete nor perfectly accurate, depending on country submissions.

z The indicator does not reflect the effectiveness of these areas, nor whether they are suitably located. Studies of the biodiversity outcomes of protected areas show mixed results.

z IUCN management categories indicate the management objectives, which activities are likely to be permitted in the area and the likely naturalness of the ecosystems. However, they are not a normative hierarchy – one type of objective should not be considered better or more suitable than another outside of the local context.

z Protected areas are occasionally recorded as points which increases the risk that protected areas will be double-counted or attributed to the wrong domain.

Further reading

For further reading consult: z Results may differ from summaries published elsewhere because of differences in the definitions of terrestrial and marine areas, the country baselines used, the definition of a country (e.g. which overseas territories are included), areal calculation technique used, how protected areas recorded as points are treated, time lag between national or regional data and updates to the WDPA, different treatment of a particular type of protected area designation and whether that meets the definition of a protected area. The WDPA also includes data from non-governmental data providers which may not be included in national databases. z OECD (2023), “Biological resources and biodiversity”, in Environment at a Glance Indicators, OECD Publishing, Paris, https://doi.org/10.1787/7afe55f8-en z OECD (2023), “Sustainable ocean economy”, in Environment at a Glance Indicators, OECD Publishing, Paris, https://doi.org/10.1787/1f798474-en z Mackie, A. et al. (2017), “Indicators on Terrestrial and Marine Protected Areas: Methodology and Results for OECD and G20 countries”, OECD Environment Working Papers, No. 126, OECD Publishing, Paris, https://doi.org/10.1787/e0796071-en. z Recent OECD Environmental Performance Reviews.