Evidence of impact of changes in climatic variables and extreme events on apes.

Evidence of impact of changes in climatic variables and extreme events on apes.</p

Projected exposure of African ape sites (n = 333) to crop failure for two scenarios.

(a) RCP2.6 near term (2021–2050) and (b) RCP6.0 long term (2071–2099). Top row: Number of years with an event within the time period. Bottom row: Number of sites and number of apes projected to be exposed to the respective number of years with an event. Maps for all four scenarios in Fig E in S1 Text. Country outline data was obtained from the R package ‘mapdata’ (cran.r-project.org/package=mapdata).</p

Geographic range for the nine ape taxa for bonobo (<i>Pan paniscus</i>), chimpanzee (<i>Pan troglodytes</i>), eastern gorilla (<i>Gorilla beringei</i>) and western gorilla (<i>Gorilla gorilla</i>).

Country outline data was obtained from the R package ‘mapdata’ (cran.r-project.org/package=mapdata).</p

Temperature anomaly across all ape sites.

Temperature anomaly is the difference to the average annual temperature of the reference period 1979–2013. Thick lines in the boxplots show the median, bottom end of the box the first quartile and top end of the box the third quartile. Dark blue: Third quartile below zero, light blue: Median below zero and third quartile above zero, light red: Median above zero and first quartile below zero, dark red: Median and first quartile above zero.</p

S1 Text -

Supporting tables Table A in S1 Text. Annual mean temperature. Table B in S1 Text. Annual maximum temperature. Table C in S1 Text. Annual precipitation. Table D in S1 Text. Maximum number of consecutive dry days. Table E in S1 Text. Number of days with heavy precipitation. Table F in S1 Text. Projected exposure to crop failures. Table G in S1 Text. Projected exposure to droughts. Table H in S1 Text. Projected exposure to heatwaves. Table I in S1 Text. Projected exposure to river floods. Table J in S1 Text. Projected exposure to tropical cyclones. Table K in S1 Text. Projected exposure to wildfires. Supporting figures Fig A in S1 Text. Anomaly of maximum daily temperature. Fig B in S1 Text. Projected exposure of African ape sites to changes in precipitation. Fig C in S1 Text. Projected exposure of African ape sites to droughts. Fig in S1 Text. Projected exposure of African ape sites to tropical cyclones Fig in S1 Text. Maps of projected exposure of African ape sites to crop failure for all four scenarios. Fig in S1 Text. Maps of projected exposure of African ape sites to droughts for all four scenarios. Fig in S1 Text. Maps of projected exposure of African ape sites to heatwaves for all four scenarios. Fig in S1 Text. Maps of projected exposure of African ape sites to river floods for all four scenarios. Fig in S1 Text. Maps of projected exposure of African ape sites to tropical cyclones for all four scenarios. Fig in S1 Text. Maps of projected exposure of African ape sites to wildfires for all four scenarios. (PDF)</p

Projected exposure of African ape sites (n = 333) to river floods for two scenarios.

(a) RCP2.6 near term (2021–2050) and (b) RCP6.0 long term (2071–2099). Top row: Number of years with an event within the time period. Bottom row: Number of sites and number of apes projected to be exposed to the respective number of years with an event. Maps for all four scenarios in Fig H in S1 Text. Country outline data was obtained from the R package ‘mapdata’ (cran.r-project.org/package=mapdata).</p

Overview of the nine African ape taxa.

Large gaps remain in our understanding of the vulnerability of specific animal taxa and regions to climate change, especially regarding extreme climate impact events. Here, we assess African apes, flagship and highly important umbrella species for sympatric biodiversity. We estimated past (1981–2010) and future exposure to climate change impacts across 363 sites in Africa for RCP2.6 and RCP6.0 for near term (2021–2050) and long term (2071–2099). We used fully harmonized climate data and data on extreme climate impact events from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP). Historic data show that 171 sites had positive temperature anomalies for at least nine of the past ten years with the strongest anomalies (up to 0.56°C) estimated for eastern chimpanzees. Climate projections suggest that temperatures will increase across all sites, while precipitation changes are more heterogeneous. We estimated a future increase in heavy precipitation events for 288 sites, and an increase in the number of consecutive dry days by up to 20 days per year (maximum increase estimated for eastern gorillas). All sites will be frequently exposed to wildfires and crop failures in the future, and the latter could impact apes indirectly through increased deforestation. 84% of sites are projected to be exposed to heatwaves and 78% of sites to river floods. Tropical cyclones and droughts were only projected for individual sites in western and central Africa. We further compiled available evidence on how climate change impacts could affect apes, for example, through heat stress and dehydration, a reduction in water sources and fruit trees, and reduced physiological performance, body condition, fertility, and survival. To support necessary research on the sensitivity and adaptability of African apes to climate change impacts, and the planning and implementation of conservation measures, we provide detailed results for each ape site on the open-access platform A.P.E.S. Wiki.</div

Projected exposure of African ape sites (n = 333) to wildfires for two scenarios.

(a) RCP2.6 near term (2021–2050) and (b) RCP6.0 long term (2071–2099). Top row: Number of years with an event within the time period. Bottom row: Number of sites and number of apes projected to be exposed to the respective number of years with an event. Maps for all four scenarios in Fig J in S1 Text. Country outline data was obtained from the R package ‘mapdata’ (cran.r-project.org/package=mapdata).</p

Mean temperature and annual precipitation for the past period (1981–2010) across 333 ape sites.

Sites where chimpanzees and gorillas occur are drawn as squares with two colours.</p

Projected exposure of African ape sites (n = 333) to heatwaves for two scenarios.

(a) RCP2.6 near term (2021–2050) and (b) RCP6.0 long term (2071–2099). Top row: Number of years with an event within the time period. Bottom row: Number of sites and number of apes projected to be exposed to the respective number of years with an event. Maps for all four scenarios in Fig G in S1 Text. Country outline data was obtained from the R package ‘mapdata’ (cran.r-project.org/package=mapdata).</p