The Surprising Gender Imbalance of Florida's Newly-Hatched Sea Turtles
- Feb 14
- 1 min read
Updated: Jun 23
Student summary by Audrey Kim
Image created by Audrey Kim
Abstract
Background: There are five different species of sea turtles in Florida, including loggerhead turtles and green turtles. Scientists said that in recent years, almost all sea turtle hatchlings in Florida have been female. They began investigating the causes of this phenomenon.
Objective: Scientists wanted to find out why mostly female hatchlings were being born in order to prevent future population problems. If this continued, the balance between males and females could be disrupted.
Method: Scientists observed nesting sites over time and surveyed areas where sea turtles laid their eggs. They measured sand temperatures and examined the percentage of female hatchlings in different regions.
Results: Studies showed that green sea turtles living on the northern Great Barrier Reef, where temperatures are warmer, had about 99% female bias. Meanwhile, those living on the southern Great Barrier Reef, the cooler region, had about 65%–69% female bias. When the incubation temperature was above 81.9°F, hatchlings developed as females. When it was below 81.9°F, they developed as males. Researchers also found that hatchlings incubated at temperatures that reached 90.1°F had higher risks of dying.
Conclusion: The reason why mostly female turtles were hatching is linked to rising temperatures caused by climate change. Sea turtles rely on nest temperature to determine sex, so increasing sand temperatures are producing more females. Extremely high temperatures can also be harmful, making hatchlings smaller and more vulnerable to predators on their way to the ocean.
