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The thermal environment experienced by developing bird embryos is heavily influenced by parental decisions (i.e., nest site selection and incubation temperatures) that directly affect the growth and success of offspring. Furthermore, ground-nesting birds construct nests where thermal variability is greatest (i.e., ground-level) thereby elevating the effects of parental decisions. Therefore, it is important to identify the behavioral responses of ground-nesting birds to thermal variation to expand management practices for this critical life stage. Our objective was to investigate how two sympatric species existing on the edges of their continental distribution behaviorally adjust to local thermal environments and regulate incubation temperature. We assessed 44 scaled quail and 76 northern bobwhite nests at Beaver River Wildlife Management Area in the Oklahoma Panhandle, USA during 2015 and 2016. Incubation temperature (Ti), paired microsite (Tm) temperature, and nest site temperature (Tn) were assessed at 2 minute intervals. We observed that quail selected nest site locations that were cooler than the surrounding landscape (F2, 30014=170.6, p-value<0.05) by an average of 2.3�C during the heat of the day (14:00). Furthermore, Tn differed among nest substrate (F2, 5201=45.88, p-value<0.05), with yucca and herbaceous plants providing the coolest and warmest microclimates, respectively. Adult bobwhites regulated incubation temperatures by keeping nests cooler than the surrounding landscape during the afternoon (T1,27863=-91.151, p-value<0.05) (i.e., mean Ti of 35.3�C compared to �mean Tm of 41.1�C), and warmer (T1, 73420=636.75,, p-value<0.05) than the surrounding landscape at night� (i.e., mean Ti of 35.1�C compared to mean Tm of 21.9�C). Interestingly, vegetation visual obstruction and cover did not differ between successful and unsuccessful nests for either species, suggesting that nesting substrate and incubation behavior may be key drivers of nest microclimates. These results suggest that quail substantially modify the thermal environment that developing embryos experience and may shelter them from extreme conditions.