Sea turtle hatchling sex is determined by nest temperature. Climate change is warming nesting beaches, skewing sex ratios toward females and threatening population viability through lack of male turtles.
Climate change is causing a slow-motion demographic welfare crisis in sea turtle populations by progressively eliminating male-producing nests. Individual hatchlings from dangerously warm nests face heat stress during development and high mortality if temperatures approach or exceed lethal thresholds. Eggs that cook in excessively warm sand represent complete developmental failure. The population-level consequence — female-biased sex ratios — will ultimately impair reproductive success as female-to-male ratios become extreme. Shading programs tested in Florida provide localised temperature reduction that shifts sex ratios back toward balance while not compromising the natural nest environment. This is one of the clearest examples of direct climate welfare harm to wild animals requiring active intervention alongside systemic climate action.