Overwintering of Hatchling Turtles in Northern Florida

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Overwintering in the nest has been well documented for hatchlings of many species of North American turtles (Gibbons and Nelson, 1978). However, most previous studies have been from localities north of Florida (from South Carolina to Canada). Lower autumn and winter temperatures at more northern latitudes presumably provide a strong impetus for hatchlings to remain buried until spring. Data concerning the existence of overwintering by hatchling turtles in Florida, where winter temperatures are more moderate (Winsberg, 1990; Table 1), are therefore of interest. Previous evidence that suggests hatchling turtles overwinter in the nest in Florida is largely limited to kinosternids (Iverson, 1977; Mushinsky and Wilson, 1992). Herein I provide evidence, both direct and circumstantial, concerning the overwintering behavior of hatchlings of three species of emydid turtles in northern Florida. Fifteen hatchling Trachemys scripta and four hatchling Pseudemys floridana, found mostly as road-kills (DOR), were encountered just northeast of Tallahassee, Leon County, in the Florida panhandle (Table 2); except for one each in 1989 and 1991, all records are from 1992-1993. Most observations occurred less than 24 h after rainfall, and all occurred within a few meters of known nesting areas. Subsequent observations on the rate of scavenging by ants suggested that dried specimens were dead for no more than one week. None of the hatchlings appeared to possess an egg caruncle (which is usually lost within two weeks of hatching). Umbilical scars were well healed and shell pigmentations were bright. These three observations indicate that the hatchlings were many weeks to months old. Trachemys scripta in the Florida panhandle nests from mid-March to early July, with a field incubation period of greater than 60 d (pers. obs.). Therefore the