MELBOURNE — Graydon Stoddard's hobby sounds cruel: Take a few birds to South Carolina, turn them loose and make them fly home in a day.

But the birds, called homing or carrier pigeons, land on their loft behind Stoddard's Melbourne home 15 hours later. They have traveled more than 500 miles at speeds of 50 mph, and usually they've won Stoddard another first place trophy from the local homing pigeon racing club.

"You treat them like you would treat an athlete," Stoddard said of his 65 racing pigeons, which have taken home 50 trophies since 1980.

"After a race, I soak them in epsom salts to help their sore muscles. I go to health food stores and buy them special vitamins and grains. I can't give you all that because then I wouldn't be competitive. But nutrition is really important. That's what makes these birds stand the abuse," he said.

Experts don't know how homing pigeons do it, but the birds can navigate their way back home from thousands of miles away. Ordinary pigeons, like those seen in parks, do not have the homing instinct. It must be bred into them.

Some researchers believe magnetic particles in pigeons' heads allow them to use the magnetic pull of the earth as a reference to navigate; others believe they use the sun.

Since the trait was discovered in one type of pigeons in the 1700s in Persia, the birds have been used to carry messages between rulers, during wars and on stockmarkets.

England and Japan use the birds to transport blood from accident victims to the hospital, so doctors can determine a person's blood type and have transfusions waiting when the ambulance arrives.

Because of the birds' keen eyesight, which can detect objects 25 miles away, the U.S. Navy is training them to look for orange buoys in the ocean that signal downed airplanes.

And in Belgium, the national sport is pigeon racing.

"They're very dependable," said Stoddard, who spends three hours a day caring for his birds. "They'll fly an average of 50 mph. They've had birds do 700-mile days in Texas when they had a tailwind and they have birds do a thousand miles in two and a half days."

Training a homing pigeon takes years, he said. They begin to fly at 4 weeks old and at 6 months, Stoddard starts turning them loose in Cocoa, Titusville and Daytona Beach to find their way home. At 8 months, they begin racing for distances up to 300 miles.

"It takes several years before they're mature enough and their muscles are developed enough to fly 600 or 700 miles," he said. Stoddard said the birds retire from racing at 7 years old. "I've had them not come back after races and I've had them come back after two years. One just came back last week after two years."

The ones that don't make it home usually have hit a power line and broken their wings, or have been killed by hawks, he said. Each racing bird wears a coded band around one leg, which allows it to be traced through the American Homing Pigeons Union to its owner.

Stoddard usually gets a few dozen calls a week from people who find injured racing pigeons. That's not surprising, he said, considering 2,000 birds from racing clubs around Florida fly over Brevard during racing season from February to April, and in the fall.

Stoddard, who grew up on a farm in New York, began racing pigeons in 1976 after meeting veteran racer John Brenner from Palm Bay. Together the two started a racing club in 1978, called the Melbourne Fliers, which has a dozen members.

During racing season, the Melbourne club competes with clubs in Vero Beach and Stuart. In the spring, the clubs have six races up to 600 miles long for adult pigeons. In the fall, they race younger birds for up to 300 miles.

Club members have special clocks that record the time the bird arrives at their home. Each member then computes how fast the bird traveled in yards per minute and the bird that traveled the fastest wins.

"Pigeon racing is very exciting for people who like birds," said Brenner, 66, retired owner of the Palm Bay Fence Company. "In metropolitan areas, this is really big. In New York, New Jersey and even California, they bet thousands of dollars on these birds.

"Here it's just a hobby because the membership is too small to come up with big money," he said.

The club hopes to attract more members and usually gives people a few birds to get started. The club also likes to stage demonstrations, help with fund- raising or give talks about pigeon racing.

"I've always been into animals," Stoddard said. "I've shown cattle and rabbits, but pigeons are the biggest challenge because they're free. You turn it loose and you can't control it like other animals. You just have to sit and wait and hope all your work pays off."