Why are Hotter Summers Putting an End to Sea Turtle Genetic Diversity?

BOCA RATON, FL - JULY 27: Sydney Jimenez, a Marine Turtle Specialist, transfers some of the more than 570 baby sea turtles, including the Loggerhead and Green turtles, into a box before they are taken out and released into the Atlantic Ocean in a joint effort between the Coast Guard and the Gumbo-Limbo Nature Center on July 27, 2015 in Boca Raton, Florida. The sea turtles hatchlings come from turtle nests located along beaches throughout Florida, which are the primary nesting grounds for Loggerhead sea turtles. (Photo by Joe Raedle/Getty Images)

Photo by: Joe Raedle

Joe Raedle

Global warming is creating a crisis in sea turtles' gender ratios, where 99% of them are being born female. Sea turtle populations have been facing a significant population decline further exasperated by climate change.

Floridian sea turtles for the past four years have been facing the hottest summers in Florida state history. Bette Zirkelback, a manager of the Turtle Hospital within the Florida Keys, noted that "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."

This startling trend shows how climate change is affecting the biodiversity within our world, while species struggle to adapt fast enough to these unnatural changes. Commonly, sex is determined during fertilization but in alligators and sea turtles something unique occurs. When female sea turtles bury their eggs in the sand, the sex is determined by the temperature of the sand along the shore. These turtle eggs will nest for around two months and their sex is precariously determined by a difference of around 7 degrees. Sea turtles that incubate below 81.86 F, 27.7 C, will be born male. If sea turtles incubate above 88.8 F, 31 C, they will be born female.

Loggerhead turtle, Caretta caretta, is endangered. A nest contains about 100 eggs. Hatchlings try to avoid many predators during their escape to the open ocean, Florida. (Photo by: Mark Conlin/VW PICS/UIG via Getty Image)

Photo by: VW Pics

VW Pics

Melissa Rosales Rodriguez, a sea turtle keeper at the Miami zoo turtle hospital, expressed her concerns saying, "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."

In sea turtle hotspots around the world, there is a huge need for sea turtle rehab centers to ensure the future of sea turtles.