"The irony is that if these animals do get released into the wild, it's a big, bad world out there, and they will have to learn how not to get entangled in fishing gear."

According to Moore, Tom and Misha's release will have virtually no impact on the world's wild dolphin population, which faces an onslaught from industrial fishing nets, decimated fish stocks and polluted seas.

But he and other dolphin experts say successful reintroduction could both increase biodiversity awareness in Turkey and set an important example for the multimillion-dollar captive marine mammal entertainment industry.

There has been a rapid increase in the number of dolphinariums and "swim-with-dolphin" programs cropping up across Turkey over the last decade.

"Turkey, being a very popular and beautiful holiday destination, is sadly responding to the public demand for that 'dolphin experience' by providing more captive dolphin facilities than anywhere else in Europe," Born Free's Galligan wrote. "Conditions in general are very poor."

Foster said he hopes Turkey will start implementing some regulations for its marine mammal facilities "because there really aren't standards right now."

One fear is that Tom and Misha, who enjoy being rubbed down and handled by their trainers, could be captured by poachers hoping to sell the valuable animals to dolphin parks.

Despite the risks, perhaps one of the great assets shared by the two dolphins is their adaptability.

"They are not lions and tigers," said Moore of the Woods Hole Oceanographic Institution. "They're fundamentally more plastic and more adaptable."

Proof of this adaptability is on display nearly every day in the congested and polluted waters of the Bosphorus Strait, which courses through the center of Istanbul.

A vibrant pod of dozens of wild bottlenose dolphins feeds here, dodging the constant traffic of oil tankers, cargo ships, ferryboats, fishing boats and yachts. Occasionally, the animals can be seen leaping and surfing off the bows of enormous tanker ships.

Misha and Tom are to be released in much less hazardous waters hundreds of miles from Istanbul. But even their "coach" doesn't know how they will fare in the days ahead.

"We just really don't know how they're going to respond," Foster said, stroking Tom's glistening hide after the 600-pound animal obediently lept onto a floating dock at his trainers' command.

Clearly, freedom will expose these dolphins to stimulation they have not encountered in years, including waterbirds, fish and female dolphins.

After a wave from his trainer's hand, Tom slipped back into the water. He issued a high-pitched call before accepting a fish as a reward. Underwater, the vocalizations of both Tom and Misha could be distinctly heard, even by the human ear.

Despite years of close interaction between humans and these highly intelligent animals, scientists have not found a way to answer one fundamental question: After years in captivity, do dolphins such as Tom and Misha want to be free?