"Hot Chicks & Cool Dudes": Is climate change affecting the sex ratio of sea turtles?

·1 hr 12 min·5 clips

Grass roots can reach turtle eggs and leave hatchlings “completely sucked dry of water.”

1. Conservation Tribe examines whether climate change is affecting sea turtle sex ratios through host Blaine Edwards’s interview with Melissa Staines. 2. Blaine Edwards hosts the Conservation Tribe, while Melissa Staines is a marine biologist and lead project researcher at the WWF-sponsored Turtle Cooling Project. 3. The episode asks how sea turtle conservation can maintain male hatchling production when nest temperatures determine sex and turtles may take 30 to 40 years to reproduce. 4. Staines says researchers still do not know how long many sea turtles live or exactly when many species begin breeding. 5. Green turtles may first breed at about 30 years old, with some potentially reaching 40 before returning to a nesting region. 6. Staines describes a middle developmental period when nest temperature determines whether an embryo becomes male or female. 7. A warm nest can incubate for about 40 days, while a shaded or winter nest can incubate for three months, changing the length of the sex-determining period from two or three days to about three weeks. 8. Staines uses “cool dudes, hot chicks” to explain that temperatures above the pivotal temperature produce females and temperatures below it produce males. 9. The pivotal temperature for many sea turtle populations is around 29 degrees Celsius, but populations can differ by 0.2 degrees. 10. In Staines’s research, shaded nests were only one degree cooler than sunny nests yet produced 75 percent males instead of 100 percent females. 11. Staines’s microclimatic-effects paper examined how tall vegetation, grasses, and bushes change the conditions around turtle nests. 12. Grass roots beneath shaded trees penetrated nests and removed water from embryos, leaving entire clutches shriveled two or three days before hatching. 13. Nest relocation must occur within two hours of laying because oxygen begins diffusing through the eggshell and wakes the embryos from diapause. 14. Staines says her honours project required watering 12 nests every day for 35 days with approximately eight or nine litres of water per nest. 15. Determining the exact sex-determining day may require swapping eggs between 27-degree and 30-degree incubators and later euthanizing hatchlings for gonad histology. 16. The episode identifies loggerheads, hawksbills, green turtles, flatbacks, leatherbacks, Kemp’s ridleys, and olive ridleys alongside threats including boat strikes, ghost nets, light pollution, plastics, and hunting. 17. Staines links the 2011 floods to lost seagrass and a green turtle population collapse two years later, while describing sea-level rise and cyclones as additional climate pressures. 18. Blaine and Staines use a conversational interview format that moves from Staines’s research background to field methods, species biology, threats, and individual conservation choices. 19. Sea turtle researchers, conservation volunteers, and climate-impact listeners would value this episode. 20. Listeners seeking general wildlife stories without research methods or marine biology may skip it.

As heard by us

A sea turtle conversation that connects reef biology with real conservation choices on nesting beaches.

Sea turtles give Conservation Tribe an accessible route into reef ecology, species risk, and the practical work of conservation. Blaine Edwards, also known as Earth Offline, speaks with Melissa Staines, a marine biologist and lead project researcher at the Turtle Cooling…

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You get a sea turtle deep dive that moves from hawksbill reef work to the hard-won fixes around loggerhead nesting beaches.

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