Reproduction is a fundamental process of biological systems. I conclude that diversified maternal investments over time and space by nesting females are reproductive adaptations that have successfully offset clutch losses, thus enabling populations of loggerhead females to meet or exceed their reproductive goal of replacement fitness. Despite devastating clutch losses caused by ten catastrophic hurricanes, hundreds of erratic thunderstorms and dozens of predation events during this study, 72% of clutches produced by nesting females on this barrier island were undisturbed-median hatching success for these clutches was an astonishing 92%. Each nesting season, females deposited 1–7 clutches over diversified time intervals at diversified locations on the beach. To deposit clutches, females migrated to the barrier island 10–12 times at unpredictable intervals of 2–8 years. Extrapolated over a 30-year reproductive span, nesting females averaged 4000–4500 eggs. I show that, rather than “putting all their eggs in one basket,” females divided eggs into 40 clutches of variable size (50–165 eggs).

Here, I apply maternal risk-management as a theoretical framework to explain multiple reproductive adaptations by loggerhead sea turtles nesting on a barrier island off the southern coast of Florida, US, from 1988 to 2004. Central to the construct of maternal risk-management is its definition of reproductive success as replacement fitness ( w = 2), the survival of one breeding daughter to replace the female and one outbreeding son to replace her mate. Maternal risk-management, an extension of r/K selection, is an indispensable tool for understanding the natural selection pressures that shape the evolution of reproduction.

Turtle predators