Rising temperatures due to global warming over the last decades pose threats to marine biodiversity. Sea turtles
are ectothermic species, and their embryonic development depends on nest conditions, particularly temperature.
Here, we explore how increasing and extreme temperatures within the 558 nests can impact the hatching success
of two sea turtle species, the green turtle (Chelonia mydas) and the loggerhead turtle (Caretta caretta), at two
tropical locations, Cape Verde and Australia, and at temperate nesting sites, Turkey and Greece. Mean nest
temperatures were higher for green turtles (30.84 ◦C) than for loggerhead turtles (29.42 ◦C) and significantly
increased in all locations as the air temperature increased. However, nests from temperate locations, such as
green turtles in Turkey and loggerhead turtles in Cape Verde, experienced higher temperatures than the nests in
Australia and Greece, reaching lethal temperatures at extreme temperature peaks. Thus, temperate populations
might be at risk as global warming continues because it is uncertain whether these higher latitudes can provide
beach habitats cool enough for successful sea turtle nesting given the projected more frequent extreme temperatures in the future
