Addressing risks to biodiversity arising from a changing climate: The need for ecosystem restoration in the Tana River Basin, Kenya

development of the Wallace Initiative, a reduced set of variables was used to minimize poten- tial autocorrelation. SDMs cannot include and account for all biotic and abiotic factors. Even though various uncertainties exist, SDMs are extremely useful for examining the future impacts of climate change on species. This knowledge is fundamental for policymakers and conservation planners. For this analysis, it was assumed that all of the species that had suitable climate space within the PAs with higher temperatures are protected in these spaces and occur in viable popula- tions. Although this might not be the case, this assumption allows for the identification of spe- cies that require more future conservation attention (i.e. those not occurring at all within the PAs). Furthermore, some PAs extend beyond the basin. For instance, the Tsavo East National Park and it’s connected Tsavo West and Amboseli National Parks. The greater Tsavo ecosys- tem may contain refugia even though the part of the Tsavo East National Park located within the Tana River Basin may not. Even if this is the case, it further demonstrates the importance of allowing species to disperse across the landscape. Conclusions This study showed significant implications of projected climate change on the terrestrial biodiversity of the Tana River Basin. When these changes in species distributions are con- sidered alongside development plans, it becomes clear that trade-offs between development and biodiversity protection may occur in the future. Various adaptation options for biodi-

versity have been proposed, including expanding protected areas to better conserve pro- jected climate refugia. Restoring lands that are projected to be refugia for plants but have already been converted to agriculture could help conserve biodiversity, facilitate species movements and contribute to Kenya’s ecosystem restoration targets. By understanding these potential conflicts between biodiversity and development, decision makers can ensure the basin is managed in a way as to ensure effective future biodiversity protection, successful ecosystem restoration and sustainable socio-economic development within this important area of Kenya. Supporting information S1 Table. Protected Areas (PAs) within the Tana River Basin. Data on the locations of pro- tected areas were obtained from the World Database on Protected Areas (WDPA). This table only includes the PAs considered in this study. (DOCX) S1 Fig. Locations of projected refugia for amphibians with 2˚C and 4.5˚C warming. A refu- gium is identified in a grid cell only if at least 11 of the 21 GCMs agree in projecting its exis- tence. (TIF) S2 Fig. Locations of projected refugia for birds with 2˚C and 4.5˚C warming. A refugium is identified in a grid cell only if at least 11 of the 21 GCMs agree in projecting its existence. (TIF) S3 Fig. Locations of projected refugia for mammals with 2˚C and 4.5˚C warming. A refu- gium is identified in a grid cell only if at least 11 of the 21 GCMs agree in projecting its exis- tence. (TIF) PLOS ONE Risks to Kenya’s biodiversity from climate change

PLOS ONE | https://doi.org/10.1371/journal.pone.0254879 July 21, 2021 19 / 25