Privately protected areas (PPAs) are increasing in number and extent. Yet, we know little about their contribution to conservation and how this compares to other forms of protected area (PA). We address this gap by assessing the contribution of 17,561 PPAs to the coverage, complementarity and connectivity of existing PA networks in 15 countries across 5 continents. We find that PPAs (1) are three times more likely to be in biomes with <10% of their area protected than are other PA governance types and twice as likely to be in areas with the greatest human disturbance; (2) that they protect a further 1.2% of key biodiversity areas; (3) that they account for 3.4% of land under protection; and (4) that they increase PA network connectivity by 7.05%. Our results demonstrate the unique and significant contributions that PPAs can make to the conservation estate and that PPAs deserve more attention, recognition and resources for better design and implementation.
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All data used in this manuscript are openly available online. Protected areas boundaries are available from http://www.protectedplanet.net/. The WWF ecoregions layer is available from https://www.worldwildlife.org/publications/terrestrial-ecoregions-of-the-world. The Global Human Footprint Dataset v.3 (2009) is available from https://sedac.ciesin.columbia.edu/data/set/wildareas-v3-2009-human-footprint. KBAs are available on request by filling out a form found at http://www.keybiodiversityareas.org/kba-data/request. Source data are provided with this paper.
The R script used to rotate and move polygons can be found at https://github.com/cemac/rotate-move-pas. The R script for random placement of PPAs can be found at https://github.com/eerhp/Privately_Protected_Areas_Palfrey_2021.
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This research was supported by the Economic and Social Research Council through the White Rose Doctoral Training Programme. We would like to thank R. Rigby for the building of the model for random placement. This paper is dedicated to the memory of E. Corcuera Vliegenthart, who did so much for PPAs.
The authors declare no competing interests.
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Data used to create Fig. 1—display of what proportion of diff gov types protect biomes with low, medium or high representation.
Data used to create Fig. 2—proportion of biome protected by each PA gov type.
Data used to create Fig. 3—complementarity.
Data used to create Fig. 4—Proportion of Human Footprint category in each gov type.
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Palfrey, R., Oldekop, J.A. & Holmes, G. Privately protected areas increase global protected area coverage and connectivity. Nat Ecol Evol 6, 730–737 (2022). https://doi.org/10.1038/s41559-022-01715-0
Nature Ecology & Evolution (2022)