The sea turtle science and recovery division at Padre Island National Seashore released 117 revived green sea turtles Friday morning into the Gulf surf.
“We wouldn’t want to release them back into the bay where they could get cold-stunned again because we’ve still got months left in the cold-stunning season,” said Donna Shaver, director of the division.
Reports of 306 cold-stunned sea turtles were documented along the Texas Coast from Wednesday through Friday, according to preliminary numbers from Padre Island National Seashore. Those that have been released were cleared by veterinary personnel at the Texas State Aquarium.
Sea turtles are ectothermic, like most reptiles, which means that their body temperatures change with the environment around them.
When mean water temperatures drop below 10 degrees Celsius or 50 degrees Fahrenheit, sea turtles can find themselves in a form of hypothermia called cold stunning.
“Usually, we will see a bunch of turtles just floating, pretty much motionless in the water, and they look kind of almost dead,” said Christine Figgener, a marine conservation biologist who studies sea turtles. “They are usually not dead yet, but they are unable to use their muscles to move around (and) they don’t have heat that would be necessary.”
Those turtles are prone to boat strikes. If they are not rescued, algae can start growing and active parasites can begin to colonize the shells.
“With time, they will actually starve, freeze to death, get stranded and even drown because they are not able to breathe anymore,” Figgener said.
Four of the hundreds of turtles that were cold-stunned were found dead, according to preliminary numbers from the Padre Island National Seashore.
The largest cold stunning event ever recorded in Texas was between December 2017 and January 2018, when more than 3,500 sea turtles, primarily juvenile green turtles, were rescued, according to the National Marine Fisheries Service.
The Texas Game Wardens in Calhoun County rescued and revived about 17 cold-stunned sea turtles last year, though they have yet to receive any calls at the start of this season, said Chelsea Bailey, a game warden in the region.
There were no reports of cold-stunned sea turtles in East Matagorda, Lavaca, San Antonio, Aransas or Copano bays, according to the National Park Service’s preliminary data. About 70% of the reports were documented in the Upper Laguna Madre/Corpus Christi Bay area and about 20% in the Aransas Pass/Mustang Island area.
When a lethargic, floating sea turtle is found, people are asked to call wildlife rescuers at 1-866-TURTLE-5, a hotline that is sponsored by the Turtle Island Restoration Network.
Because Matagorda Bay does not have a nearby rescue center, the game wardens can be called by those rescuers for assistance.
“We usually will take the boats out to get them and bring them to a safe place until they are warm enough to be released,” Bailey said.
The threat of cold-stunning varies from year to year depending on the state’s notoriously unpredictable weather, Shaver said.
“You can have one big bout or it can be distributed and it can go all the way through February, so this is just the beginning,” she said.