Data from: Variation in thermal traits describing sex determination and development in Western Australian sea turtle populations

Both the development rate and sex of sea turtle embryos depend on
incubation temperature, as all species are ectotherms and show
temperature-dependent sex determination (TSD). Theory predicts that
selection should act on populations to optimise developmental times and
primary sex ratios. In this study, we use a consistent methodology to
measure development rates and model the reaction norm that defines TSD in
three populations of flatback turtles (Natator depressus) and two
populations of green turtles (Chelonia mydas) that nest in Western
Australia. We show that development rates vary between and within species,
likely reflecting adaptation to local beach microclimates. Similarly, the
parameters that define the TSD reaction norm vary between the two species,
and among N. depressus populations, with pivotal temperatures (TPIV)
varying by 1.5 °C (29.6 – 31.1 °C), and the transitional ranges of
temperatures (TRT) varying by 1.4 – 3.3 °C. In contrast, we found a
similar TPIV for the two C. mydas populations, but a wider TRT at the
northernmost tropical rookery. Our findings support the view that thermal
parameters in geographically-separated populations of sea turtles are
broadly similar, but the variation we describe will be highly relevant for
predicting how populations will respond to climate change.