Because particular life history traits affect species vulnerability to development pressures, cross-species summaries of life history traits are useful for generating management guidelines. Conservation of aquatic turtles, many members of which are regionally or globally imperiled, requires knowing the extent of upland habitat used for nesting. Therefore, we compiled distances that nests and gravid females had been observed from wetlands. Based on records of > 8000 nests and gravid female records compiled for 31 species in the United States and Canada, the distances that encompass 95% of nests vary dramatically among genera and populations, from just 8 m forMalaclemys to nearly 1400 m for Trachemys. Widths of core areas to encompass varying fractions of nesting populations (based on mean maxima across all genera) were estimated as: 50% coverage = 93 m, 75% = 154 m, 90% = 198 m, 95% = 232 m, 100% = 942 m. Approximately 6-98 m is required to encompass each consecutive 10% segment of a nesting population up to 90% coverage; thereafter, ca. 424 m is required to encompass the remaining 10%. Many genera require modest terrestrial areas (zones) for 95% nest coverage (Actinemys, Apalone, Chelydra, Chrysemys, Clemmys,Glyptemys, Graptemys, Macrochelys, Malaclemys, Pseudemys, Sternotherus), whereas other genera require larger zones (Deirochelys, Emydoidea, Kinosternon, Trachemys). Our results represent planning targets for conserving sufficient areas of uplands around wetlands to ensure protection of turtle nesting sites, migrating adult female turtles, and dispersing turtle hatchlings. Our results represent planning targets for conserving sufficient areas of uplands around wetlands to ensure protection of turtle nesting sites, migrating adult female turtles, and dispersing turtle hatchlings.

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Interpopulation variation in egg size, clutch size and clutch mass was studied 3 years in four populations of painted turtles (Chrysemys picta bellii) from western Nebraska. Body size varied among all populations and was larger in two large (56-110 ha), sandhills lake populations than in two populations in smaller habitats (1.5-3.6 ha) of the Platte River floodplain. Reproductive parameters (egg mass, clutch mass, and clutch size) generally increased with maternal body size within populations. Clutch wet and dry mass varied among populations but largely as a function of maternal body size. Clutch size was largest in the sandhills lake populations, both absolutely and relative to maternal body size. Egg mass was smallest in the sandhills lakes and varied annually in one population. Over all populations, an egg sizeclutch size trade-off was detected (a negative correlation between egg mass and clutch size) after statistically removing maternal body size effects. Egg wet mass and clutch size were negatively correlated over all years within the sandhills populations and in some years in three populations. Although egg size varied within populations, egg size and clutch size covaried as expected by optimal offspring size models. Thus, patterns of egg size variation should be interpreted in the context of proximate or adaptive maternal body size and temporal effects. Comparisons among populations suggest that large egg size relative to maternal body size may occur when juvenile growth potential is poor and mean maternal body size is small.

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