Scientists helping sea turtles along the Florida coastline has delivered shocking news based on their experience – over the past four years, they have found no baby male turtles. Turtles, which undergo temperature-dependent sex determination (the temperature of the developing egg decides the sex) have come under extreme pressure from the intense heatwaves, and the discoveries only add to mounting evidence that the changing climate is impacting wildlife across the globe.
The past four years have seen the hottest Florida summers on record, raising the temperature of the sand, which determines the sex of turtle eggs that hatch in small nests along the shore. Temperatures of up to 27.7°C (81.9°F) will create a male while temperatures exceeding 31°C (88.8°F) will result in a female. If you have been experiencing the same intense heat that many of us have, you’ll know that 27.7°C feels like a cool dream.
While the researchers highlighting the issue are based in the Turtle Hospital rehabilitation clinic in Florida and paint a grim picture of the turtle populations in the east USA, the issue is far more widespread. Warnings from scientists about the growing sex diversity issue due to a warming climate have been heard for years, including a National Geographic piece from 2019 about turtles in Australia. However, these are some of the most concerning findings to date.
"Over the years, you're going to see a sharp decline in their population because we just don't have the genetic diversity," Melissa Rosales Rodriguez, a sea turtle keeper, told Reuters.
"We don't have the male-to-female ratio needed in order to be able to have successful breeding sessions."
Alongside other environmental and health pressures, including disease, fisheries, and coastal tourism, the researchers are now stating that more effort will be needed across the Florida coastline to help save sea turtles. If the climate continues at this rate, turtles will need continuous intervention to prevent almost entirely female populations, which would be devastating for future numbers.