Nest-site selection, hatching success and hatchling over-winter success in painted turtles (Chrysemys picta)

Female painted turtles may increase their fitness either by increasing the success of their offspring within a single reproductive season, or by increasing the number of reproductive seasons in which they can participate. Painted turtle nest-sites can be described in relation to specific microhabitat characteristics that, because of their effect on soil microclimate, may influence hatching success and/or over-winter success of hatchlings. Female painted turtles selected nest-sites based on canopy cover, understory vegetation, slope angle and aspect. Increased hatching success was associated with decreased organic content, which may serve as a surrogate for little or no vegetation cover and canopy. Turtle-selected nests had slightly higher hatching success than randomly located nests, suggesting that turtles choose nest-sites that increase offspring survival. No relationship was found between over-winter success and micro habitat, possibly due to the buffering effects of deep snow cover. The two methods of increasing fitness may not be mutually exclusive.