Distribution of the Egyptian reptiles under current and future climates

Climate change has caused range shifts and extinctions of many species in the past. In this study, the effects of climate change on Egyptian reptiles, as a representative of the Egyptian fauna, was investigated for the first time using species distribution models, relatively new tools now used in a variety of fields from conservation planning to the assessment of species’ responses to climate change. In this study, the Maxent algorithm was used to model the current and future distributions of 75 terrestrial reptile species from Egypt. The modelled distribution for current conditions for each species was projected into the future for three time slices (2020, 2050 and 2080) using two emission scenarios (A2a and B2a) from four global circulation models (CCCma, CSIRO, HadCM3 and NIES99) and under two assumptions of dispersal ability (unlimited dispersal and no dispersal). This produced a total of 48 projections for each species. Current and future species richness patterns were determined from the results using the average response across the different global circulation models to represent a consensus view. For each species, possible changes in range were calculated and used to assess future threat status. A national Red Data listing for the Egyptian reptiles was determined to show which species require more conservation measures. Zonation software was used for conservation prioritization to show which areas require more protection under current and future climates, and to assess the effectiveness of Egypt’s Protected Areas network to conserve reptiles.

Climate change is predicted to vary in its effects spatially, with some areas characterized by increased species richness while others show declines. Future range changes are predicted to vary among species and among different future projections, from the loss of the entire range (Tarentola mindiae and Hemidactylus robustus) to large gains in range (Hemidactylus flaviviridis). No species was predicted to lose its entire currently suitable range under all scenarios. Tarentola mindiae and Hemidactylus robustus were predicted to become extinct from Egypt in the future in at least one future projection. Another eight species were predicted to lose more than 80% of their current distribution in the future. According to IUCN guidelines and criteria, under current conditions, three species were classified as nationally Endangered and 24 species as Vulnerable. Although Protected Areas have greater conservation value compared to unprotected areas, Egypt’s Protected-Areas network seems to be inadequate to conserve Egyptian reptiles. My results suggest the need to construct new Protected Areas in a variety of places across northern Egypt from between Mersa Matruh and Sallum to the Gebel El-Hallal area in northern Sinai. Some Protected Areas require stricter protection in the future to counter the threats derived from climate change.