Nest emergence of smooth softshell turtle (Apalone mutica) hatchlings

I collected eggs from natural nests of Apalone mutica and reburied them in artificial nests constructed in a largeoutdoor enclosure. Toward the end of a known incubation period, nests were videotaped continuously until hatchlingsemerged. Most hatchlings emerged within a short period during a single day. Individuals emerged quickly and singly andmaintained brisk movement on the surface after emergence. Emergence times were normally distributed around a mediantime that corresponded with local sunset. Turtles emerged on sunny days when both nest and surface temperatures werebelow 36°C and on overcast days when nest and surface temperatures were relatively low and invariable. Timing of nestemergence has fitness consequences for hatchling freshwater turtles.