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Federal biologists are releasing thousands of endangered baby sea turtles into the western Gulf of Mexico, betting that by the time the silver dollar-sized swimmers make it to the oil-fouled waters of the eastern Gulf, BP will have cleaned up its goopy mess.

The U.S. Fish and Wildlife Service and National Park Service are proceeding with the annual release of Kemp's ridley turtle hatchlings off Padre Island National Seashore because Texas has not been significantly impacted by the oil spill. For years, scientists have incubated and hatched the turtles to give the endangered creatures a boost.

The risks of holding turtles in captivity at a critical stage in their life cycles could be worse than the dangers of oil more than 400 miles away, the plan's supporters say.

Hundreds of days-old hatchlings have been freed on Texas beaches since the June 8 decision. Another large group is expected to be released early next week.

The decision, however, has stirred controversy among some scientists, environmentalists and turtle lovers.

Supporters say there should only be intervention with animals directly in the oil's path, like loggerhead turtles in Florida. In 1979, after a rig blowout in the Mexican Gulf, authorities airlifted Kemp's ridleys to oil-free waters.

Critics argue the decision to free vulnerable hatchlings doesn't adequately account for hurricanes, storms or a seasonal change in current, all of which could bring the oil west and directly into their path. Nesting mothers, they say, are also at risk because many deposit their eggs in northern Mexico or south Texas and head for heavily impacted areas.

"We have raised them in captivity and learned the hard way that there are also a lot of negative potential from that," said Deborah Crouse, a sea turtle biologist in the U.S. Fish and Wildlife Service's Endangered Species Recovery Program.

However, Crouse acknowledged the release does present a risk of oil exposure. It took a team of 14 experts days to decide whether to release the Kemp's ridleys.

"It was a balancing act between the danger of holding them in captivity vs. the damage that could be done to them by the oil," Crouse said. "That's why it was not an easy decision."

The U.S. Fish and Wildlife Service said that as of Wednesday, 167 visibly oiled sea turtles of various species had been collected alive. At least 482 have been found dead, but no oiled turtles have been found in Texas.

Carole Allen, director of the Sea Turtle Restoration Project's Gulf office in Houston, is a vocal critic of the hatchlings' release in Texas. At least some of the babies and nesting mothers should be kept in captivity until the oil is cleaned, she said.

"Don't just send them out to the Gulf to die cause they're going to get oiled eventually," Allen said.

Andre Landry, a sea turtle expert at Texas A&M University in Galveston, said baby turtles swim out and attach themselves to algae mats or other floating habitats. It's possible those habitats are oiled, he said.

In Florida, because of the proximity to the oil, loggerhead turtle nests are being collected and incubated. Hatchlings are being released on the state's eastern coast, far from the oil.

"That goes in direct opposition to what's been decided with the Kemp's ridleys," Landry said.

The Kemp's ridleys have been on the endangered list since 1973 after their population was depleted from years of hunting their eggs and trapping the animals in fishing nets. They are among the smallest sea turtles, and live mostly in warmer Gulf of Mexico waters.

Their population numbers have slowly recovered. This year, there were nearly 13,000 nests — or about 4,300 nesting turtles — in Mexico and Texas, down from last year when there were about 22,000. Scientists attribute the slip to natural variation and an unusually cold winter.

Still, scientists were so encouraged in March by the Kemp's ridleys recovery they believed they might see 10,000 nesting females within five to 10 years. That would upgrade the species from endangered to threatened, allowing them to still be protected by some federal laws.

While it won't be clear until next year whether the oil spill damaged the turtles' progress, it has put upgrade hopes at risk.

Donna Shaver, chief of the Division of Sea Turtle Science and Recovery at Padre Island National Seashore has been monitoring the Kemp's ridleys for 30 years. She collects their nests from Texas beaches, incubates them and watches them hatch. Finally, she releases the babies at the precise moment when they enter a "frenzy" of activity and have extra energy from the yolk they've ingested, allowing them to get past the surf and float on the currents to their new homes.

Federal agencies have long maintained a policy that collected wildlife should be released, Shaver said.

"Any time you release hatchlings, you realize it's a perilous situation for them," Shaver said. "They can fall victim to fish, they can fall victim to birds. Only a fraction of them survive into adulthood. And this year, this is another risk they face, so it's frustrating."

Allowing the Kemp's ridleys to remain in captivity, however, creates other risks.

Early efforts aimed at recovering the species taught scientists that prolonged captivity can mess with the turtles' navigation and foraging skills, putting long-term survival in danger, said David Godfrey, executive director of the Sea Turtle Conservancy in Gainesville, Fla.

He supports the loggerhead program in Florida, but thinks the Kemp's ridleys should be released so long as Texas is oil-free.

"Everybody who is critical of that decision has a right to be critical because it's not a black or white decision," Godfrey said. "If oil comes into Texas with a hurricane, nobody knows what would happen. Is it absolutely foolproof, 100 percent, signed, sealed, delivered? I don't know. Nobody knows."