We exposed eggs of the red-eared slider turtle (Trachemys scripta elegans) to short duration (i.e., 48 hours) changes in water potential at two embryonic ages (20 and 40 days). Survivorship to hatching did not differ by substrate water potential or among treatments. Net change in egg mass, a measure of net water exchange between the egg and substrate, was affected by treatments. However, treatments had no effect on hatchling mass, carcass mass, yolk mass, or incubation period. Eggs and embryos are able to exploit beneficial short-term increases in water potential and withstand adverse ones.