Over a two-year period, we measured reproductive parameters, (vitellogenin [Vtg],
estradiol-17b [E2], and total testosterone [TT]), in plasma of 116 free-ranging Eastern Box Turtles across
their active season. We found similar seasonal variations of Vtg and E2 within females. Mid-season,
females showed a sharp peak in E2 that correlates with the putative beginning of the ovarian cycle.
Individual females lacking these expected peaks of both Vtg and E2 suggest that some female T. c. carolina
may not reproduce annually.