Florida’s sea turtle population is changing because of hot weather. Recent heat waves in the southern state have made the sand on the beaches so hot that almost of all the sea turtles born there are female. When a mother sea turtle digs a nest for her eggs on the beach, the temperature of the sand decides the sex, or gender, of the baby sea turtles, called hatchlings. Bette Zirkelbach is the manager of the Turtle Hospital in the town of Marathon in the Florida Keys, an archipelago off the southern coast of the state. Zirkelbach said that the past four summers have been the hottest on record in Florida, leading to more female sea turtles. Scientists that are studying sea turtle hatchlings and eggs have found no boy sea turtles, so only female sea turtles for the past four years. She said that an Australian study showed a similar effect in which “99 percent of the new sea turtle babies are female,” Zirkelbach said. NOAA is the National Oceanic and Atmospheric Administration, the U.S. government weather agency. NOAA’s National Ocean Service website says the sex of sea turtles is not determined at the time of fertilization, but by the temperature of developing eggs. So, if the sand is very hot and the eggs are above 31 degrees Celsius, the hatchlings will be female. If the temperature is below 27.7 degrees Celsius, then the turtle babies will be male. Melissa Rosales Rodriguez is a sea turtle keeper at the turtle hospital at the Miami Zoo. She said, “Over the years, you're going to see a sharp decline in their population because we just don't have the genetic diversity. We don't have the male-to-female ratio needed in order to be able to have successful breeding sessions.”
