This does not look good.
The nesting season for the endangered Kemp’s ridley sea turtle is ending with zero nests found on either Galveston Island or the Bolivar Peninsula for the first time in at least a decade, although the number rose for the entire coast.
The decline in nesting on the Upper Texas Gulf Coast comes as a recent study shows that the nest numbers for Texas’ official sea turtle, whose primary nesting grounds are in Texas and Mexico, are at less than one-tenth of their historic levels.
Only five Kemp’s ridley nests were found on the upper Texas coast – four at Surfside and one at Quintana Beach – during the nesting season that runs from April until the middle of July, although there are always a few late nesters.
“We’ve had some extremely high tides and a lot of flooding this year, and many times the ocean was right up to the base of the dune,” which could have discouraged turtles from digging nests, said Christopher Marshall, lead turtle researcher at Texas A&M University at Galveston.
Nesting numbers were up for the entire Texas Gulf Coast and at the main nesting grounds in Tamaulipas, Mexico, near the Texas border. But scientists and conservationists remain concerned that the increases are far below those prior to the 2010 BP oil spill in the Gulf of Mexico, the worst oil spill in U.S. history.
“We’ve got two years of increases, however it’s discouraging that we have not gotten back to the numbers we were at in 2009,” said Donna Shaver, chief of the division of sea turtle science and recovery at Padre Island National Seashore.
So far this season, 185 Kemp’s ridley nests have been found on the Texas Coast, said Shaver, who tallies every discovered nest and oversees a turtle egg incubation program on Padre Island. The real indicator of the health of the Kemp’s ridley is the number of nests at the main nesting grounds in Rancho Nuevo, Tamaulipas. The count this year is 17,000 nests, up from 14,000 last year but still far short of the record 22,000 in 2012. The record that year was barely higher than the 2009 number and far less than what scientists expected.
“It came up, but it didn’t come up anywhere close to what we hoped it would if it had grown at the same rate as in 2009 and it didn’t keep going,” said Thane Wibbles, a biologist at the University of Alabama. Wibbles said there should have been more than 30,000 nests in 2012.
“It’s still not back to its historical levels where we were seeing a 12 to 15 percent increase every year,” said Pat Burchfield, who heads the U.S. contingent of the Binational Kemp’s Ridley Sea Turtle Recovery Project and is director of the Gladys Porter Zoo in Brownsville.
Most scientists speculate that either the oil spill caused a temporary pause in Kemp’s ridley reproduction and that it will rebound, or that conditions in the Gulf have become inhospitable for the turtle’s historic population size, Wibbles said.
“It may be that the carrying capacity of the Gulf of Mexico may not be what it used to be,” Wibbles said. “I would say in five years if it hasn’t got on an exponential recovery trend then we have to look at the possibility that the Gulf of Mexico is not allowing them to come back.”
If the Gulf can’t support as many Kemp’s ridleys as it once did, he said, then the Gulf may be in trouble. Said Wibbles, “The ridley could be considered a metaphoric canary in the coal mine.”