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Sea turtles present a model for the potential impacts of climate change on imperiled species, with projected warming generating concern about their persistence. Various sea turtle life-history traits are affected by temperature; most strikingly, warmer egg incubation temperatures cause female-biased sex ratios and higher embryo mortality. Predictions of sea turtle resilience to climate change are often focused on how resulting male limitation or reduced offspring production may affect populations. In the present article, by reviewing research on sea turtles, we provide an overview of how temperature impacts on incubating eggs may cascade through life history to ultimately affect population viability. We explore how sex-specific patterns in survival and breeding periodicity determine the differences among offspring, adult, and operational sex ratios. We then discuss the implications of skewed sex ratios for male-limited reproduction, consider the negative correlation between sex ratio skew and genetic diversity, and examine consequences for adaptive potential. Our synthesis underscores the importance of considering the effects of climate throughout the life history of any species. Lethal effects (e.g., embryo mortality) are relatively direct impacts, but sublethal effects at immature life-history stages may not alter population growth rates until cohorts reach reproductive maturity. This leaves a lag during which some species transition through several stages subject to distinct biological circumstances and climate impacts. These perspectives will help managers conceptualize the drivers of emergent population dynamics and identify existing knowledge gaps under different scenarios of predicted environmental change.

The Key Largo woodrat (Neotoma floridana smalli) and Key Largo cotton mouse (Peromyscus gossypinus allapaticola) are federally endangered subspecies endemic to the tropical hardwood hammocks of Key Largo, Florida. Woodrats are considered generalists in habitat and diet, yet a steady decline in natural stick nests and capture rates over the past several decades suggests that they are limited by the availability of nesting habitat due to habitat loss and fragmentation. The more specialized Key Largo cotton mouse appears to rely on old growth hammock, a habitat type that is rare following past land clearing. In 2004, the U.S. Fish and Wildlife Service started building supplemental nest structures to restore habitat quality and connectivity for these endangered rodents, but nest use requires evaluation. We used camera traps and occupancy models to evaluate the factors influencing woodrat and cotton mouse use of the supplemental nests. We detected woodrats at 65 and cotton mice at 175 of 284 sampled nest structures, with co‐occurrence at 38 nests. Woodrat nest use followed a gradient from low nest use in the north to high nest use in the south, which might relate to the proximity of free‐ranging domestic cat (Felis catus) colonies in residential developments. Cotton mouse nest use, however, was related positively to mature hammock and related negatively to disturbed areas (e.g. scarified lands). The two species occurred independently of each other. Stick‐stacking behavior was observed at supplemental nests and, although it was correlated with detection of woodrats, it was not a strong predictor of their occurrence. We suggest that nest supplementation can be an important tool for species recovery as habitat quality continues to improve with succession.

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