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bioRxiv · 10.1101/2023.09.08.556803

The threats to reptiles at global and regional scales

Farooq, H.·Harfoot, M.·Rahbek, C.·Geldmann, J.
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Abstract

At least 20% of reptiles are currently threatened with extinction. Due to the lack of comprehensive global assessments of the group, they have been omitted from spatial studies, especially the ones addressing conservation or spatial prioritization. With the recent release of global assessments for reptiles, in this study, we calculate the probability of seven biodiversity threats - logging, pollution, agriculture, invasive species, hunting, climate change and urbanization occurring at a global scale on a 50x50km grid and their impact measured as the probability of finding a threatened species. Despite the global nature of our approach, we compartmented the terrestrial land into 12 regions and conducted separate analyses on each region. We find that despite globally low levels of intensity, climate change and invasive species have the highest impact on reptiles. But when looked at the regional level, various threats have a high impact on biodiversity, even surpassing climate change and invasives. Our study highlights the importance of going beyond measuring the intensity of threats to measure impact and also the importance of subdividing the world into smaller units and testing the impacts separately.

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Farooq, H., Harfoot, M., Rahbek, C., Geldmann, J.. 2023-09-08. The threats to reptiles at global and regional scales. https://doi.org/10.1101/2023.09.08.556803

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