Cold-stunned sea turtles return to Gulf after frigid winter storm
GALVESTON — In an idle research vessel about 20 miles from the Texas coastline, Rob Perkins, a Ph.D. student at Texas A&M University at Galveston, gently picked up a rehabilitated green sea turtle from inside a plastic tub. The turtle eagerly flapped its limbs as Perkins gently tossed it into the welcoming waters of the Gulf of Mexico.
A week ago, this turtle was one of 60 that were cold-stunned and rescued by an army of volunteers from frigid waters, victims of the four-day freeze that briefly crippled the region. On Monday, a team of naturalists, volunteers and marine scientists packed 25 of those newly healed turtles onto the Trident, a 70-foot research vessel docked at Texas A&M’s Galveston campus, and motored off shore to release them back into the wild.
“We saw them when they came in, they just looked lethargic,” said Maureen Nolan-Wilde, a master naturalist with A&M’s Gulf Center for Sea Turtle Research. “We had people from Texas Parks and Wildlife out. It was cold, their houses were damaged, but they were still going out to try to get these turtles. A&M students out there looking. … It was this amazing partnership to get these turtles back into the water.”
The freeze represented the
largest turtle cold-stunning event since researchers in 1980 began recording them nationwide, said Donna Shaver, the Texas coordinator for the Sea Turtle Stranding and Salvage Network.
Preliminary estimates Friday showed that more than 8,000 stunnings had been recorded in Texas this winter, the bulk of which were during the freeze. It was far above the record 4,613 cold-stunned turtles in Florida in 2010. The early estimates also showed only roughly half were found alive.
“This event has been unprecedented for us in terms of the severity,” Shaver said, adding, “It’s really taken its toll. We’ve had some big cold-stunning events, but nothing of this magnitude.”
Part of the reason the numbers were so big is that the population of green sea turtles — a threatened species named for the green fat deposits on their sides — has grown. But the freeze also proved “the perfect storm,” Shaver said, for causing cold stunnings.
Turtles are reptiles, so their body temperatures fluctuate with the temperature of the air. If it gets too cold, they stop moving, floating to the surface of the water and sometimes to shore.
Volunteers up and down Texas shorelines rushed to rescue any they could find, so they wouldn’t be hit by boats or attacked by predators. The bulk of the population is south around the Laguna Madre. Thousands of rescued turtles in that area were taken to the South Padre Island Convention Center. Texas A&M Galveston took in still more.
Anna DeMotte and Rhiannon Nechero, marine biology students at Texas A&M, were two of the volunteers who waded out into frigid waters to rescue the green sea turtles. They were thrilled their labor wasn’t for naught — two of the turtles they found were successfully rehabilitated and were released Monday back into the Gulf.
“One of them was out in the water, one of them was up in the reeds,” DeMotte said. “The two we found are on the boat today. It’s really special to see the whole process.”
Each of the cold-stunned sea turtles had to pass a battery of tests before being released back into the wild. The Gulf Center for Sea Turtle Research, started in 2019, also includes a hospital for nursing injured and coldstunned turtles back to health. The 60 turtles that volunteers were able to rescue were given antibiotics and monitored for days by sea turtle biologists as well as veterinarians from the Houston Zoo.
The last hurdle the turtles clear before being released into the wild is a swim test to determine that their metabolism has rebounded enough to survive and that they have full function of their flippers. For 15 minutes they are placed in a saltwater tank and observed to ensure they can dive and resurface without issue.
“We want to check their buoyancy because that can be an indication of things like pneumonia,” said Katie St. Clair, the manager of A&M’s Sea Life facility.
The rescued turtles also give A&M scientists a chance to tag them with devices that will track their movements in the wild. Green sea turtles historically inhabit Gulf waters farther south in the Corpus Christi area. Sea turtle biologists theorize that more green sea turtles have traveled north in recent years to follow the migration of seagrass beds.
“It’s good to see what environmental drivers there are on the turtles,” said Perkins, the Ph.D. student at the Gulf Center for Sea Turtle Research “Already, there’s been multiple studies that have shown decreased populations of plants and seaweed or seagrasses (which the turtles feed on) that have been moving up the coast.”
But the primary aim of turtle researchers is to save as many threatened and endangered sea turtles as possible — a mission accomplished with each of the 25 sea turtles aboard the Trident on Monday returning to their natural home.
“Trying to recover a threatened or endangered species is the long game. You’re not going to recover them overnight,” Shaver said. “So one turtle at a time you continue your efforts. You find one and then you find another and you find another. And you save them. And then collectively, the efforts of everyone with all those turtles, you hope that you will recover the species. It really literally takes a village”