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US, Mexico See Rise in Rare Sea Turtles - 2002-08-08

There has been a dramatic upsurge in nesting along the U.S. and Mexican Gulf Coast of the world's rarest sea turtle, the Kemp's ridley (Tortuga Lora in Spanish). Conservationists are hailing this as an encouraging result of a joint U.S.-Mexico project to bring the marine reptile back from the brink of extinction.

From the tiny, remote Mexican seaside village of Rancho Nuevo, to the crowded beaches of Padre Island, Texas, the Kemp's ridley sea turtle continues its slow march back from the abyss. In Mexico this year, more than 6,300 turtle nests have been found and placed under protection from human and animal scavengers.

Equally important, a record number of 37 turtles nested along Texas beaches, where hardly any nests were to be found a few years ago. The numbers are small, but encouraging. The two governments have been trying for decades to establish a secondary-nesting site in Texas for the rare animal, and, at last, they might be succeeding.

Pat Burchfield, Deputy Director of the Gladys Porter Zoo in Brownsville, Texas and the project leader, says this year "has been the best in recorded history." He puts this year's success in perspective. "When we began the project in 1978, we were calling the remnants of "Arribadas", or these nesting aggregations, anything over about 25 turtles, which really didn't meet the essence [definition] of an arribada which is a massive arrival of hundreds or perhaps thousands of females at the same time," says Mr. Burchfield. "But this year, we had actually 1,084 nests in one day at Rancho Nuevo, so that's an arribada. And when you go back to 1985 when we only had 702 nests for the entire season, that's a pretty impressive comeback."

The Kemp's ridley is not only the rarest of the world's seven species of sea turtle, but also the smallest and perhaps the oddest. All other sea turtles nest at night to avoid predators, and do so throughout the world's tropical oceans, from the Bay of Bengal to Costa Rica. But the Kemp's ridley nests in daytime and almost exclusively along a narrow, 40-kilometer stretch of beach in the village of Rancho Nuevo, Tamaulipas State.

While other turtles scatter their nests, the ridley comes ashore in large numbers called "Arribadas" which is Spanish for arrivals. Mr. Burchfield says its more numerous cousin, the Olive ridley (Tortuga Golfina in Spanish) nests in Costa Rica and India in waves of as many as 200,000 at one time, in what he explains is their way of overwhelming predators.

Safety in numbers failed the Kemp's ridley in the 1980s. Mexican villagers harvesting virtually every single egg for sale in the cities where people consider it an aphrodisiac sent the turtle's numbers plummeting. From a high of 40,000 turtles nesting in a single June day in 1947, the nesting numbers dropped so low that scientists thought the ridley was doomed. So began the longest and apparently most successful Mexican-American conservation effort in history. It included transplanting or "head-starting" Mexican turtle eggs to Padre Island, Texas, where they were hatched and released in the hope they would come back to nest in that new home. Now, almost all eggs in both countries are guarded during their six-week incubation period and then the baby hatchlings are escorted into the sea to keep predators away. So far, in Mexico this year more than 367,000 baby turtles have been released.

At Padre Island National Seashore, where U.S. Geological Survey sea turtle station leader Donna Shaver has spent roughly half her life waiting for the turtles to return, this year was also a watershed. "We're very optimistic that over the long run we're going to continue to see an increase in numbers," she says. "We've gotten turtles returning from the head start project; we've got an increasing population worldwide of Kemp's ridleys; good public education effort ongoing; good patrol efforts in South Texas; many entities working together to try to find the nests and the nesting turtles. And so I think with those things combined the future is looking good."

The Brownsville Zoo's Pat Burchfield says the cooperation of the U.S. shrimp fishing industry has helped enormously. The Kemp's ridleys feed on the bottom where the shrimp live and often get caught and drowned in shrimp nets. Now federal law mandates trap doors in all shrimp nets to allow the turtles to swim free. After initial resistance from shrimpers, Mr. Burchfield says, they joined the program and even went to Mexico to build an additional turtle nesting conservation camp.

Les Hodgson is the Kemp's ridley recovery project leader for the United States' largest seafood trade association, The National Fisheries Institute. He says when they saw the turtle's plight, the shrimpers decided to help. "A number of years ago we realized the only real solution wasn't going to take place in a law court, [fighting the net's trap doors called Turtle Excluder Devices TEDs] it was going to take place in the court of public opinion," says Mr. Hodgson. "And the solution was to attempt to bring that turtle back. What we saw is the real solution to the turtle problem was to protect the babies on the beach and get them back into the water."

With the dramatic increases in nesting and increasing U-S and Mexican conservation efforts, plus wider public awareness, scientists agree that this most primitive of sea turtles, virtually unchanged for the past 50-million years, can now look forward to life on earth for at least a bit longer.