Researchers explore how rising temperatures may affect desert birds in southern Africa. Exposure to extreme heat may harm birds that inhabit hot and arid areas. To determine the acute and chronic effects of increasing temperatures on desert birds, Shannon R. Conradie, Andrew E. McKechnie, and colleagues examined physiological data for 11 bird species and behavioral data for 3 species that inhabit the Kalahari Desert of southern Africa. The authors mapped the risks associated with heat exposure under past, present, and future climate conditions, which were simulated for the periods 1050-1850, 1850-2014, and 2076-2100. Although the southern African arid zone was not projected to exceed any species' heat tolerance limits or increase the risk of lethal dehydration and hyperthermia during extreme heat events, the risks of chronic, sublethal effects of heat exposure were projected to significantly increase for 3 species with available behavioral data: Southern Fiscals, Southern Pied Babblers, and Southern Yellow-billed Hornbills. During chronic exposure to sustained hot weather, adult Southern Pied Babblers are predicted to lose approximately 4% of body mass per day, endangering the species' persistence. Southern Fiscals and Southern Yellow-billed Hornbills are predicted to experience declining breeding success and to produce smaller offspring. According to the authors, the study predicts significant declines in avian biodiversity in the Kalahari Desert by the end of the 21st century.
Article #18-21312: "Chronic, sublethal effects of high temperatures will cause severe declines in southern African arid-zone birds during the 21st century," by Shannon R. Conradie, Stephan M. Woodborne, Susan J. Cunningham, and Andrew E. McKechnie.
MEDIA CONTACT: Andrew E. McKechnie, University of Pretoria, SOUTH AFRICA; tel: +27-727777572; email: aemckechnie@gmail.com
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Proceedings of the National Academy of Sciences